Check out this Food and Wine article by Jacques Torres on tempering chocolate. I use my microwave just not on full power. For milk chocolate I use 70% power and for white I use 60% power. The most important thing is to go slowly. It will take several minutes but the chocolate will not get a white bloom when it dries and it will be shiny and dry quickly. The white bloom doesn’t change the taste of the chocolate; it just doesn’t look as appealing.
You can practice tempering chocolate when making almond biscotti, triple chocolate biscotti or turtles.