You may want to visit a few garage sales in your area to get an idea of what the going price for certain items in area.
In our area
paperback books $.25
hardcover $.50 to $1.00
children's books softcover $.10 to $.25 - hardcover and board books $.50
glassware like mugs, vases, misc glasses $.25
children's clothes - you can price nicer quality namebrand outfits or items $2 to $5 - things like t-shirts, leggings, shorts $.25. I recomend sorting by sizes and keeping nicer items separate from the "play" clothes.
You can also put a bunch of socks, onsies, etc. in a zip lock and just write on the bag $3 for all.
If you have toys with parts, for example the fisher price barn with all the animals and the farmer, but all the parts in a zip lock bag and attach it to the barn, it'll prevent pieces from falling out and hopefully keep kids from playing with them.
It's good to group items and then just make one set price. For example, just one sign for the books. All the play clothes in a bin that says $50 each.
Make sure you have help the day of the sale.