The site does discuss sex A LOT. Do not give out any personal information to anyone for any reason. If someone asks where you live, be as general as possible - I live in the Northeast U. S. for instance instead of I live in New York. I live in a major city would cover any information anyone needs to know about you.
There are trolls here, like anywhere, so if you see someone saying something truly outrageous, don't respond to them at all.
There is no major secret to the site just be active - You will get to know people that way - Since you are 16 I will say the site can be very sexualised but you can avoid that on the general site - Ok for a young girl like you most important thing you do is go to settings and hit the "Allow PMs only from the people I follow" to keep the creeps away.
It's gets kind of wild out here so brace yourself, don't be afraid, have a backbone. There's some alright people on here, not so alright people even some trolls, and ridiculous dumb baiting questions/answers.