first lay out the t shirt and cut a v neck ( u should be able to figure that out on ur own)

then flip it over. cut out the back of the shirt to about half way up the back

then from the excess cloth u just cut off, cut for rows about an inch wide. pull each of them to stretch them then tie two of each of the strips together at one end

starting at the top where u cut to, make 1/8 inch diameter holes down each side about an inch apart

now take the two strips u have and tie one end of each on to the top hole on each side then lace back and forth going through the holes goign down, tie and ur done