Start with plump, but not too ripe, strawberries that have nice greenery on the end. A long stem is nice, but these are usually more pricey, and not necessary for dipping. Rinse them off, and dry them completely. This is a crucial step, as the chocolate won't adhere well to a wet berry.
There are several products for dipping fruit, but you can do just as well with chocolate chips and a little Crisco. I use Nestle's Semi-Sweet Morsels, and about 2 TBSP of Crisco for every cup or so of chips. The tricky part is melting the chips correctly. I have to be honest and tell you that I don't have a double boiler, and have never used one in my life! To melt the chips in the microwave, place them in a microwave safe container and zap them for 30 seconds at a time. Stir after each 30 second increment, and it's a good idea to pull them out when they still look just a little chunky, so you don't burn them. Stir them well after taking them out, and this will disburse the heat well enough to smooth it out.

I have an amazing little gizmo that I bought on QVC that melts the chocolate evenly, and is perfect for dipping fruit. I don't know if they still carry it (bought it a couple years ago), but here's a picture (made by Cook's Essentials)
So after you have dried the berries well, stick a toothpick through the end of it and dip into the chocolate, letting the excess drip off. I like to give it a little twirl and shake to get even more off. There is such a thing as too much chocolate! Invert the berry, sticking the toothpick into a piece of styrofoam (I put waxed paper over the styrofoam to keep it from getting nasty). You can also just hold the berry by the crown to dip, and lay it down onto waxed paper, not using a toothpick at all. I just prefer the control of using the toothpick to dip and twirl.
Place the berries into the refrigerator for an hour or so for the chocolate to set. If you don't want to do anything fancy to them, that's it! Place on a pretty plate for presentation and enjoy!If you want make them a little more decorative, you can use almond bark to make swirls and loops on top of the chocolate. Melt the almond bark in the same manner as the chips. I have tried using white chocolate chips before, and just couldn't seem to get the melting down. Almond bark works wonderful - just let it cool for a few minutes before putting it into a sandwich baggie to decorate (or pastry bag - but I'm lazy and hate cleaning these!). Cut a very small hole in the corner of the bag, and holding the strawberry by the toothpick, squeeze the bag while turning the berry. Don't squeeze too much - depending how thin it is, and how warm it still is, it may just come out on it's own. Hold it over the container that you heated it in to avoid a big mess and save what you don't use. Don't try to be perfect - the beauty is in the zigzags and loops and swirls. Do you think anyone will notice before shoving it in their mouth anyway? :)