1. Cut your intake holes in the bottom.
2. Cut pallets along the center line and the long ends and centre piece in half
3. Fill barrel until you can't get in one more toothpick.
4. Cut that much more wood again and have it stacked ready.
5. Get air compressor with a 2 metre wand blower attachment
6. Get a Tiger Torch.
7. Fire up the wood with the tiger torch from the bottom air intakes. Go around the bottom.
8. When the wood "shifts" inside the drum. Put the blower wand in a air intake and hit it with 20psi of air.
9. Put out your smoking eyebrows and split ends.
10. Repeat 8 and 9 until you can load the barrel again.
11. You should end up with a barrel half full or better of coals. Keep hitting it with air.
12. Keep body butter handy for your peeling skin. Cheeks and nose especially.
The coals will last in excess of 8 hours if you don't hit them with air frequently. The "fire" might be gone but those coals are going to last and they are HOT. Pallets seem to have good hardwood in them. At least the ones I had did.