Before the start of the blog, I'd like to thank this blog for motivating me to write it.
However, this blog is quite outdated in many factors like the rating system, and people starting cp in 2020 may have trouble following these. Therefore, I would like to write new tips for doing well in codeforces. The goal is getting to candidate master, or rating 1900.
I would write this in 4 steps, but the most important thing here is Practicing hard. You won't get to 1900 if you don't practice, you don't have to do it on the blog's way, but you should practice.
Step 1: from 1000(grey) to 1200(green)
First, read introduction to the new rating system and judge your skill. Note that you'll need to take part in about 5 contests to judge your skill. If your rating is under 1200, read the next part and practice.
If you use div3, you'll need to solve 3 problems in 30 minutes. That means you should solve div3C in 15 minutes. To practice it, you may choose 1000~1200 rated problem and try to solve it in 15 mins. If you have no idea in 15 mins, you should see the editorial.
If you use div2, you'll need to solve 2 problems in 30 minutes. The practice methods are the same, but do it in 1100~1300 rated problems and 20 mins.