After downloading the free Instagram app to your phone and linking it to your social networking sites of choice, such as Facebook and Twitter, you'll need to check on your settings. Remember, when you find that perfect moment and want to share it, you won't want to spend time fussing around with the basics, so think hard about the times and circumstances you're most likely to use the app.
In the main photo screen, there are three main toggle options immediately accessible from single buttons: front/rear camera, portrait/landscape setup and various flash options. You'll be changing these often, depending on your location and proximity to your subject, which is why they're available on the main interface.
One setting to consider, here, is whether you want to be "Public" -- the default -- or a "Private" user. If you choose the latter, you'll be asked every time you OK a shot whether or not you want it on your public feed. You can also choose how you'd like to be notified, Facebook-style, whenever people react to your feed.
Whether or not you are a public user, you can still connect to and follow other users. There are search options available to find your friends automatically on the service, via interest keywords (for example, "knitting"), your Facebook or Twitter lists, your phone's contacts, and even popular users the app will suggest for you itself.
Finally, Instagram is committed to joining location-based apps like Foursquare, Yelp and Facebook Places, so you'll need to decide whether you want your pictures to appear automatically on a map of your exploits as you upload them -- or even just for certain users. Everyone's privacy needs are different in the online world of today, but Instagram has options for everybody.