Unless you know how to sew by hand. You are pretty much going to have to buy a new one. The bikini material is too thick to sew on a household machine, in order to replace the Velcro. And the glue on Velcro wont last because of the top heating up in the sun will soften the glue and it will just fall off.
'87 YJ, 4.2L built and bored, 8" of lift, 8.8 rear, AX15/NP 231J, Tom Woods drive shafts, Flat fenders, 12,000LB winch, Custom bumpers, Rattle can paint job. Never completed...