Just as you start, first boulder together with TNT barrel
First section. In the beginning, as you cross the first rope, on the platform there's a TNT barrel with the second boulder and a whipping amigo
After boulder 2, you climb a wooden ladder, then go right, find first a TNT barrel, then other two, then go up, then, on he left, just under an obnoxious tomahawk amigo, you find boulder 3. I usually bring it on the very bottom floor together with all the TNT barrels, just to be sure not to waste trys.
On the top of this section, together with a red boxeur, you can find boulder 4, and TNT barrel next to it (if you accidentally blew it up, you can bring the boulder down and blow it with some other barrel you brought down for boulder 3).
On the end of the first section, next to the right pointing wooden arrow, you have boulder 5, but no easy TNT barrels in the vicinity, so just pick it up and fall down to blow it together with boulder 3 (note that a single TNT barrel can blow many boulders together, so you can survive some errors here and there). Note: if you couldn't blow the 5 boulders before starting section 2, you will have to restart, because there's no way of bringing boulders back or barrels forward (Bottomless Gorge, you know).
After the end of bottomless Gorge, at the beginning of section 3, you can find boulder 6, on the right of the right pointing wooden arrow; if you climb on the left, you can find the TNT barrel a few hops away: bring it down and throw it on the boulder standing right under the arrow.
Once you blew boulder 6, hop again up left where you found the barrel and proceed left: you will change section and find two TNT barrels and some blue amigos, kill them and hop on a platform on the left where you'll find boulder 7 and the needed TNT barrel (note: if you proceed left you'll be back on section 1 BEFORE Bottomless Gorge).
Starting from where you blew boulder 6, if you follow the trail, hopping left, up right, up left, up, up on ladder, up right, you'll find boulder 8 (kill the amigos in the surroundings). You can blow it with a TNT barrel up right of it (on another platform) throwing the barrel from the left of the platform where you picked it up.
This is a little tricky. You have to arrive at the end of section 3, just before the entrance to the last section, you'll see a rope going down: take it and go down, down, down, down, where you'll find boulder 9; pick it up and throw it on the platform up right (be careful: if you miss, the boulder will break on next throw and you'll have to restart). Bring then it to the right, under the rope, use it to climb the rope, get the treasure and then the barrel; bring the barrel down, position the boulder on the far right and blow the boulder throwing the barrel from the far left.
Last boulder is after the rumble but just before the end of the level: pick it up and bring it back to the room before the rumble, where there are 3 barrels to blow it and get the deserved badge (please note that the platform in the middle of the room will intercept your barrel and make you miss).