What size gaerne sg-10 boot would l wear if l wear size eight and a half shoes?

l would not go for those boots. l can see that u r youngish by the size of ur shoes.

Go for alpinestar Tech 6, Tech 7 or Tech 8.

The Gaerne boots r very high & u may even find that they come just about to ur knee. They r also very wide at the top & u would have to tighten them so much u would damage the boots.

Alpinestar make fantastic boots & r quite slim & short, the tech 10 is a bit bigger though.

They r same foot size as Gaerne but the ''neck'' kind of thing is shorter & thinner.

But if u still want Gaerne, just go for size 9.

l would not suggest spending that much on boots u will grow out of very quickly though. It will be a waste of money.