Hi just finished a 60 degree triangle one block wonder - i was advised to use largeish pattern with background - if the pattern overlaps you don't get the right effect apparently. (will try and post pictures)
I battled to "see" the end result from the fabric until I was shown the mirror trick ... two mirror tiles stuck together with tape like a hinge and then you open the mirrors and put them on the fabric as you move the mirrors around you can see the type of blocks you will get - its a bit like a kalidescope. Hope this makes sense!!
The actual quilt was easier than it looks, the cutting and deciding on the design was the difficult part. My design wall was a sheet pinned to the curtains in the lounge!
I sewed the pieces in columns and then you had a straight line to join them.
It was a super pattern to do and I would certainly do it again.