So guys...

how do I buy an account on here from a new user and be sure it's safe

 

First of all, welcome to Sythe! I've moved your thread to the Sythe Support section

The most important thing to know is any account you buy can be recovered, there is no 100% way to make an account safe for the buyer. I recommend just paying a little extra to buy from someone ridiculously trusted, and no trusting a random. The account can be recovered at anytime, whether a day later or a year later.

I'd recommend you read this guide and pick up some tips. It's slightly outdated but still has some good information: http://www.sythe.org/threads/asapgangs-guide-to-purchasing-selling-a-runescape-account.1554491/