Whether you're a veteran smoker or a total beginner, there's never been a better chance that you're going to be legally buying marijuana in the very near future — if not already. With new recreational and medical legislation in nine states as of November, now is the time to experiment.One major beginner mistake is to rush the whole thing, says Bruce Barcott, deputy editor at Leafly . "Everybody’s first instinct is to go in, grab the first thing they see, and get out because they’re nervous about visiting a dispensary," he says. "[Instead],try to make yourself take time and talk in a genuine way with the person across the counter."That person — your "budtender" — is there to help you find exactly what you're after.But that doesn't mean it's not overwhelming when you're trying to pick something out. For starters, you've got three different types of marijuana strains: In general, a sativa will give you more of an uplifting, energizing high, and so it tends to be better for things like depression. An indica usually offers more of a relaxing, sleep-inducing sensation, so those are "your classic insomnia strains," says Barcott. And then you've got hybrids, which may be sativa- or indica-dominant, but tend to incorporate elements of both types.Strains also differ on their concentrations of compounds. For instance, sativa strains are usually higher on THC than indica strains, which is why they're so helpful in countering chemotherapy-related nausea. However, these also tend to have lower levels of another compound, CBD , which can counteract the less appealing side effects of THC, such as anxiety. Without that CBD buffer, these strains are more likely to cause reeling thoughts when taken in larger amounts.Whatever you settle on, though, you should be aware of your dosage, Barcott says. And your ideal dosage will depend on the form of cannabis you're using. When smoked or vaporized, cannabis hits your system fairly quickly (often within a few seconds). So you'll know pretty soon how much you feel comfortable taking — and then stop there."But with edibles, start low and go slow," Barcott says. Here, doses will be in milligrams, and a high dose may be all the way up to 70 mg. However, if you're trying edibles for the first time or just trying a particular product for the first time, Barcott suggests starting at around 5-10 mg, waiting around 45 minutes, and then seeing how you feel. For some people, the effects can take up to an hour to come on. So don't start scarfing down a second piece of chocolate at 20 minutes, or you might find yourself very overwhelmed come minute 90.Before you get there, though, you've got to get your medicine. To help give you an idea of what you might see at your local dispensary, click through to learn about 30 of the most popular marijuana strains and what other patients find them useful for.