Sizing the Wig
The size of your doll's wig may not seem very important, but figuring out what size you need is the first step to purchasing a new wig. A doll wig needs to fit snugly over the head -- too big and it will slide off, too small and it won't fit at all. The universal way to figure out a wig size is to measure the circumference of your doll's head along its "wigline." Place your tape measure on the doll's forehead and then bring it down to pass by just above the ears and meet at the back of the head where the nape of the hairline would be. Record the measurement in both inches and centimeters, though most wigs are sized by inches.
Wig Materials
Picking the right material depends upon the look of your doll. For traditional porcelain dolls, mohair is the most common choice for that soft look of delicate curls. When working with fashion dolls or ball-joint dolls, shining saran tends to be the standard. There are human hair wigs available as well for a more realistic look. While these are the general rules, don't be afraid to do something different with your doll.
Style and Color
Once you have your size and material picked out, it's time to select your style and color. It is best to start with the style of the wig as most wig sellers will have color variations available. If you can't find the right color, you can dye wigs but this may undo any styling. If you are thinking of styling the wig, always buy a longer length wig to give yourself more to work with.
Attaching the Wig
When putting on your new wig, start at the forehead and gently pull it towards the back of the head to stretch it over the whole scalp. While you want your wig to fit snuggly on its own, sometimes you want a little more support. Film Velcro -- which you can buy from ball-joint doll specialty stores - can be glued to your doll's scalp and sewn to the caps of wigs to make for a more secure hold while still allowing you to change wigs. If you wish to permanently attach a new wig, gently apply a layer of glue to the scalp with a paintbrush before placing the wig. Allow the glue to dry for 24 hours before styling.