If it is 100% cotton wash it in cold water and before it spins after the rinse cycle take it out dripping wet and pull from each end and sides and let it drip dry. I have found this works for me. It might not be the right way but sometimes home remedies work.
I had two brand new, and expensive, dress shirts that got washed in the warm/hot cycle, then tumble dried. They shrunk significantly, particularly the sleeve length. I used the above advice, with one extra step that worked wonders. I hung the wet shirts onto pretty sturdy hangers (like a man’s suit jacket hanger), buttoned the sleeves, and placed 2 1/2 lb. weight plates (the kind you put on dumbbells, etc., bought at Wal-Mart for a couple of bucks) into each sleeve and slid them down to the cuffs. Allowed the shirts to air dry, and viola, the sleeves are normal length again! Maybe even a bit longer than originally! At any rate, it salvaged the shirts. I’m sure you can use other items for the weights.
Another thing you can do is get a brush and some viniger.
1. Dip the brush in the viniger\
2. brush the viniger all over the shirt…as if you were painting a fence
3. wash it again and then air dry ^_^