How can I make DIY curtains for my laundry room?

What size of windows? For privacy or for decorating?

Are you wanting to sew a rod pocket or do you want exposed rod clips?

If sewing them myself, I would definitely pre-shrink the fabric, by washing & drying it. Laundry room curtains need to be washable.

A shower curtain is a good option for this area. Some are very pretty and of course, they are durable and washable.

Look for a fabric that is white clouds on a blue sky or just blue sky or just blue curtains. You can make the curtains by using fusable tape or by sewing hems and headers. Glue or sew (zigzaging over) on some thin cording and miniture wooden craft clothes pins. If your creative self wants to continue you can cut out clothing shapes from fabrics backed with a fusable. Iron the "garments" along the cording. You curtains will be unmistakably laundry. If this doesn't appeal to you there are many laundry themed fabrics available to you.

You could make drop cloth curtains! Here's my tutorial: https://www.aratariathome.com/blog/diy-drop-cloth-curtains

Try using kitchen or hand towels, make a rod pocket at the top, or clip on rings. So many styles, colors, or prints and all washable. Easy, cheap, and lasting.