There is a large range of going about it. From buying a ready to go setup from Privex to setting up your own server.
I'm still trying to figure out what my witness should look like in the end. It is probably a little early for me to confidently give an opinion on how to best run a witness.
At least I like to have a chat with you after "your learned your lesson"
Ofcourse :)
There are a few guides out there to read up on the topic.
This one by @klye is a little older but I think it provides a great picture of what you are getting yourself into:
https://steemit.com/witness-category/@klye/the-complete-noob-guide-to-steem-witness-setup
Privex is someguy - or??
Yes. Thats his business.