Jungle Path

It's good to start with Raptors, it's an easy clear with E. Warding the bush behind Red Buff so you can quickly react on ****er jungling and ask for help from your team.Start Red Buff and use both Potions, then head to Crugs. Always remember to ktie crugs by going in around the big one so the smaller one can't reach you.

If bot side: After getting Level 3 you can contest for a Bot gank or head to mid and try to contest there. After ganknig Bot is succesful Scuttler Crab will be spawning in some seconds.If you didn't gank bot you can head to Mid and then get the top Scuttler Crab and get top side camps or contest for Top Lane gank.
If top side: After getting level 3, if enemy to pushes it will be an easy First Blood, remember to slow him with red before hitting Q. If you gank succesfully go take the top side Scuttler Crab or if you headed to mid go for the bot side Scuttler Crab and clear bot side camps and maybe contest for a Bot Lane gank.

Don't forget to engage with ult and don't instnatly press Q, wait for a second before Q so you get the full potential of snare and stun.

Amumu's Q hit range is really big so always try hitting those even with a small angle because it also has a wide hitbox.

Be careful while Q because you maybe hit too far and go into death by mistake.

Don't forget you can probably 1v1 everyone cause of your burst damage. Don't try not to waste all abilities when you fight 1v1, just use everything and get the pick on him/her