1. Practice first with a gluten-free mix for cupcakes or brownies or pizza crust to get the hang of how different the batter/dough is. You'll have the comfort of knowing that it's not that you've done anything wrong because you followed the directions but you get to see first-hand that it's a completely different baking experience.
2. Get a multipurpose gluten-free flour blend in a box or bag. Heresy for some, I know. There are some amazing gluten-free bakers out there who have spent a great deal of time, energy and money perfecting different ratios of gluten-free flour by volume or weight for different applications. Personally, my house is too small and my patience too short. I like Arrowhead Mills and Pamela's the best. I hear Trader Joe's has a gluten-free flour blend and I look forward to trying it. Bob's Red Mill also has a flour blend, and they seem to have better market penetration that their competitors, so you can find it more places. I discovered Arrowhead because it was on sale at my local grocery store one time, and other than having some notable flaws in the recipes on the back of the box (their blueberry muffin recipe doesn't actually say when to add the blueberries, for example), I've found that their blend does a great job in general. Pamela's is great too, though usually more expensive. Know that if you buy gluten-free Bisquick, most of your stuff will taste suspiciously like Bisquick. This is good if you are making pancakes or biscuits, but not so good if you are making pizza crust.
3. Arithmetic is your friend. When using a gluten-free recipe that uses a host of different flours, add up the total the recipe calls for and use your pre-fab gluten-free flour blend instead.
4. Review the ingredients on your flour blend to see if it contains xanthan gum or guar gum. If I convert a regular recipe to gluten-free and my flour blend does not contain one of these items already, I add about a 1/2 a teaspoon of xanthan gum per cup of flour called for. You can use less for"flatter" foods like cookies and pizza crust. Xanthan gum gives the batter some stretchiness to help it be more like its gluteny cousin. If my flour blend already includes one of these things, I do not add any more.
5. If you are trying a new recipe, make half a batch if possible. These ingredients are expensive! Experiment with less and if it doesn't turn out well, you'll only be half as annoyed.
6. You'll have greater success with flatter items and smaller items. Things that don't need to rise, like cookies and pancakes, seem to be easier to get right than breads. Likewise, cupcakes and muffins are more successful than cakes and full-sized quick breads, though quick breads are pretty forgiving.
7. Brace yourself for wetter, stickier batter. If you are used to making regular crusts, bread, etc., gluten-free batter and dough will seem all wrong. It's wet and sticky and wants to climb up the beaters of your handheld mixer and doesn't spread in or on the pan like other dough/batter. You are not doing anything wrong. If you didn't follow tip number 1, go back and buy a mix to practice with first.
8. Chocolatey baked goods seem to be less identifiable as gluten-free. I don't know why that is. If you feel like you need your gluten-free offering to "pass," make a chocolate thing.
9. Some baked goods are naturally or quite easily gluten-free. Lots of peanut butter cookies have no flour whatsoever. It's easy to find cornbread recipes that use only cornmeal or cornflour. Flourless chocolate tortes are all the rage, And believe it or not, I've found a number of Martha Stewart recipes that rely on cornstarch instead of flour.
9. A note about cross-contamination. If you are a long-time baker of regular items, you'll want to invest in a new rolling pin and surface onto which to roll out your items. I've never seen a rolling pin that didn't have Flour of the Ages embedded in it. Wooden cutting boards and surfaces can also hold the flour. Get new ones and declare them gluten-free, keep them wrapped when not in use, and label them. As for baking sheets, I use parchment paper on my cookie sheets, and I've recently bought some silicone cupcake things that I will keep gluten-free as well.
10. Buy the Gluten-free Bakehouse pie crust from Whole Foods. My friend Jessie made the pie with it and I couldn't tell that it was gluten-free. For whatever reason, making gluten-free pie crust intimidates me. Live's too short to be cowed by pie, so if there is a thing out there that solves the problem or makes you feel better, by all means do it! I did make a gluten-free Mi-Del Ginger Snap cookie crust at Thanksgiving. it was easy and good, so that's always an option. I've also made a crust for quiche out of thin slices of potato, a restaurant I frequent, Seven Stones in Media, PA, uses corn tortillas for their quiche crust, so there're more than one way to work around the pie crust dilemma.
* If you are looking for insight on bread-making, check out the YouTube from Pamela about how to make bread from her mix. Not that you can't use a bread maker or make gluten-free bread from not-a-mix, but the main things I learned were that a) I don't have a butch enough mixer, and b) boy, doesn't that batter look funny! No kneading! So sticky!