OK so here's a quickly
thrown together attack (my first ever so bear with me please!)
first you need to find a tshirt 1 or 2 sizes larger than you normally wear (i'm normally a size xs/small and i used a size medium tshirt)
mine looked just like this except it was pink
now you need to cut your shirt along the pink lines i drew in the pic below. (i also took out some fabric from under the sleeve/arm part of the shirt and sewed it for a more fitted look, but it is not necessary)
now you need to cut a strip of fabric 4 inches wide and 100 inches long (the length will probably vary depending on the size of your garment) then fold it in half horizontally and sew the two edges together.(this was the most time-consuming part for me!)
all you have to do now is sew your white fabric along the black lines drawn below (the sleeves, the bottom of the shirt and the neck)
and now your done!
you also may want to sew some designs or appliques on the sides of your shirt i.e. hearts, skulls, lightning bolts etc.
sorry for my bad computer drawings
i put this together as fast as i could!
i hope this was helpful! let me know if anything
i'd also eat
to see how yours turns out!