Explore your tutorial experience.
Since where you land when you first log in keeps constantly changing, and Yours Truly can't really keep reincarnating with new alts to test the waters each time, this section is a big vague on the specifics. But when you log in to Second Life for the very first time, there is bound to be some kind of basic tutorial thingy to get you up to speed on things like walking around and changing your appearance.
As tempted as you may be to take the Eddie Izzard technojoy throw-out-the-instructions-and-figure-it-out-yourself approach, you will find that your experience will run more smoothly if you do all the silly little exercises so you can get a feel for how to make things go. Because you're likely to look even more silly if you go straight to the mainland and still don't know how to walk properly.
Find a decent place to call Home.
You first Home will probably be chosen at random. From that point forward, until you change it, that is the place you will return to when you hit the "Go Home" button on the Map, or where you will appear when you first log in with the "My Home" location selected as your entry point.
You can change the location of your Home by selecting "Set Home to Here" under the World menu. However, you can't set it just anywhere--it has to be either under land you own yourself, or at a spot called an Infohub. If you're not quite ready to buy land just yet, you can either settle for where you were dropped off (which might be fine) or you can find another Infohub and set your Home for there.
But how do you find another Infohub? The easiest way is the Search function. Click the Search button at the bottom of the screen, select the "Places" tab and type in "Infohub" and click the "Search" button just next to it. The various Infohubs will appear, ranked by traffic. (Hint: the highest traffic is not always the best place, because it also means that the place is more crowded and therefore prone to more lag.) Clicking on each entry will give you a picture and a description. Decide what looks good to you and click "Teleport" just underneath the description to go there and have a look. (I personally recommend the Isabel Infohub, which is right next to The Shelter, a little club that caters to those just starting out.) At any rate, when you find an Infohub you wouldn't mind returning to, set your Home there. You can always change it later if you find a better Infohub, or wind up buying your own place. (There are also certain Groups that own land that allow certain members the ability to set Home on that land, but that's a little too complicated to get into in a quick five things.)
Don't be afraid to tell people that you're a newbie.
At the very least, people will be more likely to forgive you for being clueless and less likely to suspect that you're somebody's alt. Many people will, in fact, be incredibly helpful and glad to take you by the hand and show you around. The most important thing is to expect nothing. Remember, people in SL aren't obliged to give you jobs, money, advice or the time of day just because you wandered within chat range of them. Just tell them that you're new and let them decide how they want to respond.
Better yet, find places that cater to newbies.
Once again, the Search function can be your friend. While a search on "Newbie" will land you all kinds of things--some useful, some less so--an even better way to get oriented is to search the Events listings. You can search inworld by hitting the Search button and selecting the Events tab. In the little menu for "Category" select "Education". This will bring up a listing of scheduled Events that are classes. Some will be advanced classes in things you're just figuring out, but you will find a number of classes specifically for people who are just beginning. Note when they are and Teleport to them. Try to get there a little early, especially for classes of limited size, because sometimes the landing point isn't exactly where the classroom is.
By the way, you can also see the same Events listings (minus the Mature listings) on the secondlife.com website. You can even teleport directly from the website through the SLURL provided.
Take advantage of as many freebies as you can find.
Okay, maybe not every single freebie--otherwise your inventory will explode to ridiculous proportions in a short period of time. But when you're just starting out, having some halfway decent hair, skin and clothes will do wonders to get rid of that newbie look. Freebies are a good way to get a feel for what's available and what's worth spending money on before you graduate to actual cash money. Just do a search for "freebies" in the Places tab and you'll find loads of stuff right off the bat. (I recommend Vienna Freebies and Sarah Nerd's Freebie Paradise for starters.) There are also established shops that provide free sample hair and skin to avatars that are less than 30 days old--if you can find them, grab them.
Some 'freebies' will require a payment of L$1, but given that a Linden is less than a penny (the exchange rate is roughly 250 Lindens to the US Dollar) it's close enough to free. You might be able to grab a few Lindens from a Money Tree if you remain determined to spend absolutely no cash money on anything in Second Life.
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