Hi, I am newbie myself, so not sure if what I say helps at all. I think I saw this in a lesson somewhere, most likely here at GT.
Anyways, just barre the E and B strings, this part is easy and the angle method does help a lot. Then start by stretching your middle and ring finger over the fret board. I have noticed that I can barre the E and B strings, but when I try and do the rest of the chord i loose pressure on them, thus the stretch! I am slowly building up strength to do both as I start to add more pressure with my stretch.
Hope I made sense and this help. Good luck.