Wigs Gluing, sewing, or rooting?

I have no info on rooting silicone caps but I’ll say leaving the hair on the skin will result in a bulkier wig overall, whereas gluing the hair on a cap will give you more control as to both the density and directional flow of the hair. A few factors, then, if you are looking for volume or for a more structured style, or making wigs for large or very small dolls...?

 

I have had one wig that was sewn with the skin. As Havra said, it's bulkier. It was okay. I like having more control though and since the hair isn't a set length, I would probably cut the hair and make a wig cap to glue it to. It might be a bit more work, but it might look better in the end.
I haven't rooted into silicon caps, so I can't give advice there.

 

I have both types here, the ones that were glued and the ones that were still attached to the skin and sewn into shape. Thirding what was said, the sewn wig is way bulkier and doesn't sit as well on the doll head because of that.
So I'd also say, better shave it from the skin and glue it onto a self-made cap

 

The simplest and quickst method would be to simply leave it on the skin, sew the skin into a wig and then style it. Loads on-the-skin wigs are in use and can look great. several of my dolls have them and they have a lovely soft look.

Teddy

 

I never did a wig, but I am planning to make one with rooting at the part and edges and gluing everywhere else. IMO, the "best way" depend on what hairstyle you want to achieve, as there is a direction for the hair and the time factor. (You could root everything, but it would take you months. You could glue stuff, but you may not have completely change the hairstyle. You could make the wigcap with the skin: it will be bulky. So there are advantages and disadvantages for everything)

(For rooting, you may not need silicone, cf that tutorial: Making "lace" realistic wig for BJD | Whispering Grass on Patreon)