folding a seam:

the stretch and roll method is really the best method, but it takes practice.
basically you start the fold, then while slowly folding it with the roller, you "steer" the fold with the far end.
just don't stretch it, merely "steer" it.

if you can't deal with that, then tape a cleaned wide strip upside down to the table. (rough side clean and up)
trowl a layer of glue on it. let dry. place "easy release" (blue or purple) masking tape over the glued surface.
use a ruler and make lines.
cut the strips, which are now ready to apply and not sticky wet noodles. just peel slowly as you work.