Ok so for RC, here are my 2 cents:
1) Start reading newspapers - Skim read and build up your speed. This may sound like a vague start, but I found it helped me focus tremendously on the content without getting distracted. Don't waste time jotting down points or para summaries. You should train yourself to summarize paras in your head and follow the development of the passage.
So for example, para 1 spoke introduced hypothesis, para 2 had contradictions with two examples, para 3 was a consensus etc. Princeton Review advocates taking down quick notes - I'd say avoid, it slows you down.
2) Art/social issue passages - read more in depth. Science/economics articles - read a little faster keeping in mind key place holders (remember defining portion of paragraph so you can refer back quickly for a specific question). The sci/econ articles generally have more direct answers as opposed to art/history/sociology ones.
3) Try this one out, see if it works for you - Read the first question quick before beginning the passage. If its a "Provide a headline" or "whats the main message" it'll make you keep the bigger picture in focus throughout. If its targeted at a sentence you'll know where to refer immediately while reading through.
4) My colleague who just got a 760 recommended this - She said no matter what the questions is, even if its one of those "What is the author implying.." type questions, the answer will always be found within 2-3 sentences. Its quite literally true - for questions in which I get stuck on in RC, I remember what she said and focus a bit harder in terms of just spotting that one or two key sentences. Really helps.
Also check this link for brief tips on RC:
https://www.topmba.com/articles/gmat/GMA ... OK,1CCKD,1