I will tell you a simple strategy.
1) Determine what level of RC you are comfortable with. To do this you can go on gmatclub and search for RCs with difficulty levels. Start from 600 level, then if u get all questions right, then do 650 level and then 700 level. If you get more than one wrong in a level then that level is where you must start.
2) Then do 4-5 RC per day of that level from a good source. In gmatclub you can filter by level and source. Eg you can select 700 and OG. OGs are the best source as their questions are authentic and their answer choices are rarely wrong.
3) Do read all the explainations of all questions from smart person(kudos will decide that), unless you are sure why you have selected or discarded all the options. This will help you improve your reasoning capbilities required in RC. Also, it will give you an idea how to think about a particular question and how to improve upon your thinking process. Read answers from 2-3 people.
4) Always use timer, but dont worry about timer while solving question. Focus on accuracy. You must try to get the correct answer each time. Timer is just a reference you will use after you have solved the question to see how much time you took overall. A good measure is around 2 minute per question. This should include reading the passage as well. For 3 question RC, 6 min and for 4 question RC, 8 mins is required.
5) This is the most important thing to do. Read the passage thoroughly. Do not skim. This is very important as it will give you a proper understanding. I take around 3.5-5 minutes on reading the passage which is way above what coaching people and books recommend. But then I take less than 1 minute to do each question. Most of the question I do in 30-40 second. So my overall time always is less than 6-8 mins. But accuracy dramatically improves.
Hope it helps. Best of luck