Strings must be straight when you do a restring. When you string a racquet the cross strings have a natural tendency to bow as you move down the frame. It is vital to straighten these strings when you are doing the crosses and also at the completion of the restring. This will ensure you are producing the most professional restring with the least amount of tension loss. It does not matter if you use your fingers or an awl to straighten the strings. Babolat make a special straightning tool, however it is not essential to have one. I have seen many stringers using a blunt awl or an old screwdriver.
If you racquet strings are not staright when you receive an pay for your restring. Then give it back.
For all your restringing needs, call Tennis Gear Online.