Save it as .png and use the stickers bot from telegram

How do you save it in the correct size?

Whatever program you're using, just put the size to 500x

there are millions of apps to change to png :3 well correct size max are 512 x 512 also can change with a app like PicsArt if you have to upload it you should send it as a file not as just picture ah forgot thats the way for mobile telegram xD

All i can draw is a stick man lol a 4k stick man...

I use paint.net, but basically once you crop out the image, the stickerbot says to add a transparent layer and one of the sides of the image must be 512px exactly; and the other side either 512 or less

https://www.youtube.com/watch?v=yUfj3nC89m8

After minute 4 comes an explaination how to use that bot.