Sometimes I do straight sets other times I use pyramid sets. Just depends on how I'm feeling.
When pyramiding I use this scheme
Set 1 60% of top weight warm up
Sets 2 and 3 use 80% of top weight pre exhaust
Sets 4 and 5 top weight taken to near failure
When doing straight sets build up on the volume. So once I can get 3x8 with a certain weight I go up to 4x8, once that is achieved go up to 5x8. Once that is achieved I up the weight so I'm back down to 3x8 and start the cycle again. Very effective because I'm cycling the volume and total amount of reps.