How can you get birds to use your bird bath?

The optimum depth for water of a bird bath is two-and-a-half inches. Less water makes it difficult for birds to take a bath; more makes them afraid.

if you want birds to use your birdbath, place it in an area in your garden where it is lightly exposed on one side, they like privacy so yes, make it shallow to an extent where if your eyes were level with the rim of the basin, you would only see the birds head.

the colour and size matters aswell, too colourful and it will attract predators, too low to the ground and it becomes too accessable by cats/dogs, basically when placing a birdbath, treat it as though you were looking for a place out of the way and inconspicuous, a place you could do whatever you wanted with the feel of no threat, take into consideration the things in your area that could threaten a birds well being in your garden.