I invented this hack called leapfrogging. The idea is to write three sonnets (or songs, or whatever) and then go back and revise the second two. Now write a fourth and a fifth Then rewrite the third and fourth, etc... When you have written 10 this way, then go back and choose the best two and revise those. Start again with a new sequence.
The idea is to improve by two ways: doing more writing, and going back to revise. A new piece will be better because you've written more, and because you are also going back to revise. The idea is that the first one will not need to be revised: that's just to get your feet wet.
9 10 write
7 8 revise
9 10 revise
Choose two poems to revise from among 1-10.
Repeat entire process 5 times
or something like that.
A revision should be complete: every line should be different.