Grab your 2 part epoxy clay and cut off two equal amounts. You can use polymer clay, if you prefer, but it's not nearly as strong and durable as this stuff.
Mix them together well. Don't skip this or your clay will not harden properly and all that time, effort, and materials will have to be thrown out.
And then roll it into a cute little clay ball. If the colour is even, it's properly mixed.
Pull a smidgen off your ball-o-clay and roll it into a mini ball. This will become a tooth so size appropriately, say less than 1cm in diameter or so. Really depends on your personal tooth size preference.
form it into a teardrop shape, with one end pointy and the other rounded.
Now, keeping that shape, flatten out the top and bottom edges. This is an incisor. The larger end will be the top of the tooth (the cutting end) and the tapered bottom is the root.
Grab another small bit of clay, a bit bigger this time.
Roll it into a tear drop shape as well.
Now curve it slightly. This is a canine tooth.
Continue doing this until you have a full complement of teeth. Check the shape periodically as they harden. It may be easier to shape them after they have stiffened up a bit.