This kind of wooden hanger works best; the bar helps keep it balanced.
Mark out the spots where you want to put your hooks; I did 25 but 20 is easier to work with.
Here are all the marked holes.
Use a cordless drill with a really small bit to drill out the holes.
Make sure when you are drilling out the holes to keep the hanger clamped down so it doesn't move. And to have something under it so it doesn't wreck your work surface.
Start threading the hooks into their holes.
Use the pliers to tighten the hooks up and make sure they are all facing the right way.
Some of the hooks may poke out the back of the hanger and from the drill coming though there may be burrs.
Use the foam strips to cover the holes. This will also keep the hanger from marking up the wall it hangs against.
Just remember that you need to balance the necklaces on the hanger so it doesn't tip to one side.
Im working one one now where the hanger and hooks haw been painted to match the decor of my sisters room.