You are going to need a tefflon foot for your machine!

OR a roller foot, or even wax paper works. Vinyl STICKS!

most vinyl has a knit backing and that is what you will be sewing into (assuming right sides together sewing, not top stitching), so use the strongest ball point needle you can find.

i suggest using wax paper or tissue paper BETWEEN the layers of right sides together seaming, and wax paper or tissue paper ON TOP OF the vinyl as you sew.

yes, agreed, use the teflon foot, but if you don't have it (they are cheap on the internet, tho, so get one asap), the paper helps.

test your patterns, there are no do-overs in vinyl... the holes in the stitching show when you remove them and also weakens the integrity of the material.

yes, there is a bias on vinyl and there is a "grain" / direction. don't just use this like a craft fabric, use it like real fabric to get the best results on your garmetn or costume.

use a glue stick or staples or something to baste yoru seams into place BEFORE you sew and be sure to stop frequently to check pull on fabric.

clip the curves GENEROUSLY, this will be the key oto your success.

if your design allows it, use piping , this will help your seems firm up and keep shape. you can even just use seam tape on the INSIDES of the seams, doesn't have to be decorative... just use it to help keep seams strong and in shape.

don't forget heat can be your friend and the cold can be too. a good strong blow dryer, hot oven (be caaaareful) or alternatively ice, ice packs, and the freezer are going to help you get some fantastic results.

i love love love sewing with vinyl. you can really push the fabric to do what you want.

good luck