I just picked this up yesterday as part of the Humble Bundle, any tips for a beginner?
Just go out and have fun exploring! When I first started, I got myself sorted with the basics and then I gathered enough materials and built myself a small base underneath the LifePod that you start at. I could then put lockers inside and store stuff that I picked up.
Stay away from the back of the Aurora. That's Reaper territory!
And if the game starts to get really laggy, you'll need to clear out your cache files. Keep in mind that doing so resets the resources that have spawned in the game. But it improves the performance drastically! There's a tool that can do that here.
Honestly, the game is just beautiful and it's so much fun just discovering stuff. But it can also be terrifying at the same time. Just enjoy!

I'll get some more tonight, but I ended up stopping at around 1400m because I was worried that without the upgraded jets on the PRAWN, that I wouldn't be able to get back up again because the drops were getting steeper and steeper the further in I went. I ended up over 1000m away from the Cyclops in the end, and that was already about 1000m into the Lost River, so it stretches down far!