To make an '80s off-the-shoulder sweatshirt, cut part of the neck area off of an over-sized sweatshirt. The sweatshirt should be loose, because a tight sweatshirt will not give an '80s flair.
This project only requires a pair of scissors and a sweatshirt, and is great to do for an '80s-themed party, or just as a fashion statement.
Step 1: Prepare the sweatshirt
Pre-wash and dry the sweatshirt to make sure it won't shrink later.
Step 2: Mark the neckline
Spread the sweatshirt out flat, and use a washable fabric marking pen or tailor's chalk to mark about 1-inch in from the stitching on the sweatshirt's collar.
Step 3: Cut the neckline
Use sharp scissors to cut inside the marked line.
Try it on and adjust
Put the sweatshirt on and see if the neckline falls off the shoulder as desired. If a deeper cut is needed, repeat these steps to get the desired look.