Whole milk makes the creamiest ice cream.
If you want to use low fat (not fat free) milk add 1 package unflavored gelatin to 1 cup of the milk that has been heated, let it dissolve for at least one minute and add that to the remaining milk mixture before adding to the ice cream maker.
Make sure that your ice cream maker is chilled (if you have one with an insert like mine)
If you're using pure vanilla extract in your ice cream be careful how much you add, too much will inhibit the ice cream from freezing properly (Trust me on this one, I learned the hard way with a batch that nearly refused to freeze)
Always store your ice cream in an airtight container.
I haven't moved onto custard ice creams yet (cooked base made with eggs) when I so I'm sure I will have more to add to this list.