Fly up to the ledge behind the waterfall and go through this tunnel until you find a tree stump. While going there you'll see that these bugs will follow you and attempt to harm you, but will only do so if you're in your Bee form, otherwise they'll just run, or rather fly away. You'll notice that there's a hole in the stump, so jump down inside it. You'll land on a sloping platform, so just head down it.
If for whatever reason you've lost your costume, then there's another one down here, so get it if you need to. The ledge here is pretty high, but you can climb up it with the Bee suit. As Bee Mario you can also walk on flowers, so if you want those coins then fly up there and get them.
Farther up are gaps and a whole bunch of honey. Try your best not to get caught in the honey, as it acts like the mud from the Good Egg Galaxy and will drastically reduce your speed. If you happen to go off the edge on accident, just fly back up with your Bee Suit, but just make sure you don't go down too far because there's a black hole at the bottom. Go through the launch star at the end to go to the next planetoid.
You'll land on a lily pad here, so avoid the enemies and the water to access the flower with the stem. Jump onto the stem and shake the Wii remote, which will send you far up and onto the flower above. Jump across these flowers and get the Star Bits if you want to. Head up to the larger flower and shoot through the launch star.
On this planet you're allowed to climb up the honey combs, so do so and get to the top where you'll find a Piranha Plant. If you manage to kill it, then a vine will pop up. Head up it (by shaking the Wii remote) and you'll land on a large leaf, where the Bee Queen will explain she's really itchy. This is because there are five star chips on her, so just climb on her body and find them all. After that, a launch star will appear, so go through it. You'll land on a planet with a bunch of Toads who'll give you a power star they found.
Jump across the stream and ground pound the jumping pad to reach the sling star. Spin around it and go farther up. You'll see a Wiggler ahead, ground pound the switch there and a bridge will appear (and the Wiggler will topple over). Jump on the Wiggler to get some star bits and head over the newly formed bridge.
Ground pound the second switch on the other side of the bridge and half of the platform you're on will drop. This will allow you to Wall Jump up them, so do so to get to the top. Head up the hill here and you'll eventually come across two wood walls that you're able to wall jump up. Once you get to the top, spin around the launch star to get to the next area.
Head down this structure and when you're on the bottom of it, jump high enough so that the gravity on the planet below it will pull you towards it. Keep on heading down, dodging the Wigglers. Go through the sling star which will send you to the next planet. Head down the stump with a hole or get the star coin which will release a rainbow star. If you're in a hurry, just go down the stump.
Head up the slope here and use the swing to jump across. If you swing high enough you'll be able to get to the ledge above without having to go the other way around. If you go the slow way, then just wall jump up to the area above. Head left and make sure you dodge the bug here. Ground pound the red switch, which will cause the windmill to rotate. Jump onto one of the moving platforms and head up. You'll see one of those annoying bugs with another on top of it. You'll have to ground pound the two twice until they're both dead. After this, you'll get a star.
Go down a bit and go into the tunnel that is behind the water fall. Either dodge or kill the three Mandibugs that'll charge you and head to the end of the tunnel, where the Queen Bee will explain the situation with the antagonistic Mandibugs. She'll then cause a Launch Star to appear, so go through it.
You'll land on a platform that is hovering in the air. If you need the Bee Suit, then get it, if you already have one, then spin around the flower to the north to get launched in the air. Fly the rest of the way to the other platform above, get the coins if needed and repeat the same process.
The boss of this level Bugaboom will then appear. Right away fly in the air and ground pound his body, which will cause him to become quite angry. He'll then start to fly around the stage dropping bombs, so avoid those. If you get harmed, you'll lose your Bee Suit, though there's another one somewhere on this stage. Because the boss will be high in the air, it's suggested that you go onto the honey comb and wait until he comes around so that you can jump off and ground pound him. When he starts to go faster, you'll have to do so a while before he comes around so that you can get your timing right. Once you ground pound him a total of three times, you'll kill him and get a star.
Start the race against Cosmic Mario by heading straight. Keep on long jumping so that you'll gain a whole bunch of speed. Don't worry about going the wrong way, as the large arrows will point in the correct direction. Head up to the tunnel behind the waterfall and head down the stump at the end of it.
Backflip off of the block and then do it again to get to the ledge above. Continue down the path and, as aforementioned, avoid the honey. Long jump if you can, though note you can't long jump if you're in honey. Get to the end and obtain the star.
Head up farther and jump on the swing. Swing until you get the purple coin and jump off right then. If you're able to, land on the platform with the purple coin and then head down on the opposite side to get five more coins (18/100). Wall jump up the walls here to get three more coins, then head right to get two (23/100).
Jump off of the ledge and get the five coins behind the fountain (28/100). Long jump to get the two coins behind the waterfall then head down the ledge here to get one more (31/100). Head south past the Piranha Plant and sticking things and then ground pound the small stone structure, which will cause a vine to sprout up. Head up it by shaking the Wii remote, where you'll launch off and land on another vine, meaning you'll have to yet again shake the Wii remote to get across.
Ground pound the stone here, which will reveal a jumping platform. Ground pound the jumping platform, but make sure you're on the edge, because you'll have to find a way to get on top of the block above (try spinning when you're at the peak of your jump). When you get on top of the block, backflip to get the coin above (32/100). Jump off of the block and head into the water area. You'll see three coins above the fence. Just jump while in the water rather than going on top of the fence so you won't fall off.
Head to the left and behind the large tree to get five more purple coins (40/100). Now jump on the ledge here and collect five more coins (45/100). Be sure you're careful, because you might fall off and be sucked into the black hole. Go into the little pond below and collect the coin there. You'll find two more behind the log, bringing your total to (48/100).
Now head south while on the lighter green grass and get the three purple coins up there (51/100). You now have over half of the coins! Head back to where the Wiggler is and ground pound the red switch. Kill the Wiggler if you wish and head over the bridge. Once you get across the bridge, you'll see another switch to ground pound, do so to make half of the platform behind you drop. You'll see two purple coins that are in the corners of the top of each portion. To get the first, wall jump on the right wall and spin to get it. Now head upwards and do the same thing to get the second one (53/100), however you probably don't need to spin here.
Now head up again and collect the two others at the top (55/100). Head up the hill and collect the three on the grass. Wall jump up the two walls to get three more (two of which are on the top of each wall, rather than in the middle (61/100).
Now head back down and back flip up the platform here to get two more coins (63/100). Stay up here, and eventually the camera will situate itself so that you see a couple blocks below, each with a purple coin on one. Jump down so you land on the uppermost one, then on the one below that to get both of the coins (65/100). Head down even farther, though don't go through the stump. Head to the back of the tunnel here and get three more purple coins (68/100). Now head back and go through the stump.
When going down the stump, don't move at all, because the coins are on a set path so that you don't have to. There are five here (73/100). Get the two behind the green pipe (75/100). Backflip on the wall here, then at the peak moment spin to get on top. Jump across the first gap, though DON'T GO IN THE HONEY! Get the coin there, then jump across the second gap to get two more. Cross the third gap and then get six more coins and a 1-up (84/100).
Backtrack across the gaps, though make sure you don't get caught in the honey. Jump off of the ledge and then go through the green pipe. Jump off the ledge here and go back up the two vines. Jump on the second jumping platform and go through the sling star. Go back up by wall jumping then go on the hill above to get three more purple coins (87/100). Jump down off of that ledge (to the right) and slide down the hill. Get the coin here then continue on to get more coins (92/100). Jump down and get the purple coins here. One of them is above the fountain, so either backflip or wait until the water goes up so that you'll be lifted there. Before you go down, make sure that you have (97/100), then jump down.
Now for the last time, spin up the two vines to get to the other side. Now, situate yourself so that you are positioned in the correct spot so that you'll slide down through the three last purple coins (100/100). The star will be right there, so collect it