Minecraft Hacks Externally?

How would I run minecraft hacks so that when I am asked for screenshots of my .minecraft and my options and versions screen that it will not show a hack client.

I saw someone using something like this on my friends server not so long ago but the person has been banned for now due to excessive abuse of a fly hack. My question How do you do this?

1 install a hacked client
2 go hacking
3 if they ask for a screenshot move your hacked client folders out of the .minecraft and take a screenshot.

Get a clean .minecraft, put the file in a different directory. BOOM!!! When they ask for a screenshot, take a pic of that clean .minecraft!

Most of clients have .legit command. Then just take a screenshot and prove them that way!