Julie, I was the same way about sewing triangles for a long time. Even bought thangles. But one day I decided I was going to conquer my fear. One of the best lessons I was taught was to cut your triangles bigger than required (maybe 1/4 to 3/8 bigger) then use your square-up ruler to cut them to the correct size. Also use a walking foot if you've got one. Practice on some scrap fabric until you get the hang of it. Good Luck!