|I'm helping a young neighbor learn to sew, and this tip I learned from who-knows-where popped up in my brain. I would happily give credit if I could remember where I picked it up . . .
When sewing something new or challenging, whether it be a new kind of seam, seam finish, a slippery fabric, a new technique of any kind, focus only on the next 3" to sew.
This reduces tremendous amounts of anxiety! Assuming that you've properly prepared the seam for sewing with basting or pinning or whatever it requires.