With Valentine's day just around the corner, I wanted to do project perfect for the holiday. Chances are, we all have an unused t-shirt or sweater taking up space in our dresser. I used an unloved, clearance sweater purchased from Gap (not unloved anymore, though). The felt only costs thirty cents, and can be found at Walmart or any craft store.
You can use stencils for the letters, but if you don't have them start each one with the same size block and draw your letters on the back before you cut out.
Sewing Tip: You can tell the letters here are slightly too close together. When you're working with stretchy fabrics, always do the placement step with garment on. That way you'll know how much stretch there is. If you do this step with the garment flat, your letters will probably be too far apart when you put it on, which will make your word look distorted.
You could also use embroidery thread, but if you don't have any...several strands of regular thread work just fine.
Using a contrasting thread on the heart will make it stand out.