Here's how, if I were doing some heavy hacking that required to be untraceable here's how I would accomplish this...
1. Use live OS, only save files on remote servers
2. Never hack from home network, always use open wifi networks or hotspots (ever connect to a hotspot that other people are connected to their open shares are always fun)
3. When it comes to hotspots, do not use ones that put you on camera!
4. Connect to private VPN on a random or hacked network
5. Always use proxies/tor on the VPN network
6. NEVER go to the same spot again
Follow those steps and most people wont ever be able to find anything on you, you would be an internet ghost
Oh yes, it may be slower, but never use USA proxies or public proxies for that matter. Set up proxies on hacked servers and go that route.
If you live in the US, then always use out of country VPN's and proxies, jurisdiction issues tend to put a damper on things as well.