I found this shirt in the target pj/workout clothing section for $5.
Then I put it on and marked with dots where I wanted the slits to start and stop and cut my slits. (That's a blue shirt on the inside so it would be easier to see.)I don't think jersey knit ravels, but just in case I did zig-zag the raw edges. So there you go! I tried it on under a t-shirt and you can't see the edges of the slits at all. I think I'll have to make another one!
Edited March '09: Well, I've made a few of these now and after a few small changes, I have to say, my favorite shirt has the slits all the way on the sides by the side seams (still going up fairly high). It's a muscle-man shirt from the men's underwear section and it's proven to do perfect double duty as a nursing liner and layering shirt...protecting modesty from the top of the shirt to the bottom!
In other news, Three rolled over today! A pretty amazing feat considering I hardly ever lay him on the ground. He is named Three afterall. :o) Too many other little feet for me to be comfortable with it unless I am right there next to him. So, hurray Three! He's such a big boy. As Two says, "he's almost a grown-up now!" Not quite, but he does just happen to be 21 wks today!