How do pro players do those tiny and fast moves while csing?

It's the "Wiggle"!

This is a technique used by mid-high elo players for a variety of reasons.

Doing it usually just requires fast klicking and mouse movements around your champion but you also have to know what you are doing and why you are doing it.

So about how they do it: They simply move their mouse back and forth in a straight line while clicking on the end.

Here is a video of LastShadow teaching a mid-elo player (D4) how to do it.

Here are some reasons why the wiggle is used:

• You keep your APM high and remain in the flow of the game (same reason as to why stutter-stepping is used)
• You can react with a punish since you usually keep near the edge of the range of a certain ability/champion. One larger step and you can get off an (unexpected) ability.
• It applies mental pressure on the opponent since it looks like you're planning something.

The last point is important since most players on Diamond or higher will no longer mainly rely on their reaction to avoid abilities but instead they try to anticipate when an ability will be used through reading the opponent.

Reading a constantly wiggling opponent is much more difficult since he constantly looks "aggressive" which can force an unexperienced player into a highly defensive playstyle.

There are various factors in making those movements, I'll go through the basics and you may ask in the comments or do some research based on the terminology I use.

Part1: Settings

Before going into the game, you may wish to adjust your mouse settings and get used to them.

Most pros use 1200-1600 DPI settings for their mouse with "Enhanced mouse precision" turned off (it's on by default on almost all modern computers).

Anything beyond 1800DPI or below 600DPI is not recommended.

Set windows mouse speed meter to the middle one if you have mouse drivers which controls DPI or adjust accordingly if not.

Always have your in-game mouse settings set to 50 (middle) and screen ratio at 1:1 of your display ratio.

Part2: Actually moving your mouse

You may find it difficult to constantly make good decisions on where to move next but it doesn't matter too much for now.

Avoid setting your target destination too far from your champion and constantly rightclick within 300 units of your champion. This is why we need enhanced precision off, your mouse is now at a specific distance moved IRL : pixel moved on screen ratio, making it easier to spin your cursor around your champion without losing control.

Part3: When/Where to move

I could write a book on this but here's the general rules:

Avoid entering attack range of opponents
Avoid auto-attacking opponents in range of their caster minions
Avoid being near enemy caster minions Stand behind your casters to avoid blockable skillshots (Ezreal, Blitzcrank) Stay from your minions to avoid being caught up in waveclear (Syndra, TF)