Watch the G Slow Blues: 3rd Chorus online guitar lesson by Robben Ford from Riff Revolution
So the third chorus, first four bars, I start out with a little theme. Once again, that tells me what to do next - we're changing to the IV chord. I do this so much, especially in blues. It's just made for it! So that's my established theme, and then I play it slightly differently.
After that, I find a new theme. There's a little development here, choosing to do it in a double time kind of way. It's taking something very simple, a little twist of what was happening before time-wise, and making something fresh out of it.