Are you looking for strategy, time management or ways to familiarize yourself with the question types or even the 'types' of essays you'll come across.
There are strategies that are successful when you're consistent with them...but the most beneficial way to improve your performance on RC is to increase your reading speed. This is true for many reasons but comes down to a couple of points.
1) the more quickly you read the more focused you are, which makes you more engaged, and thus focused, with your task at hand. More focus means you're entire being is involved: mental and intuitive, and you will more likely answer in alignment with what you perceive as correct answer choices.
2) It's the old 80/20 rule, about 80% of the answers come from 20% of the essay. Therefore, you're wasting your time comprehending and retaining essay content. The time you save by reading efficiently will also allow you more time to engage in answering questions, which ultimately is what you're getting scored on.
We're scheduled to offer an online speed reading course soon for GMAT/GRE test takers. We also work remotely with great success on this very thing with students, if they're not in a city where we have a tutor.
If you find you need an RC edge beyond what you're working with, don't hesitate to contact me directly.
Good Luck!
Bara