What are your Investment Rules?

[Snoopy]

As I read posts across the board, I've seen people refer to the rules they follow. Seems like people vary between:
- no rules at all
- follow your gut instincts
- then all the way up to carefully designed thought-out plans

So I'm curious to know, what are some of the rules that you follow? Are they hard and fast rules that you NEVER deviate from? Or they more guidelines, to be tweaked constantly?

These are some of the rules I follow off the top of my head.

1/ Make sure any company you invest in makes a net profit after tax (or is imminently projected to do so).
2/ Try and invest in 'pairs'. Pick the two best companies in any industry you want to invest in and split your investment between both. This should prevent you from thinking you can always pick the one best company to invest in when you are constantly reminded of what the opposition is up to!
3/ Buy a company that you wouldn't mind holding on to if the share market closed for five years. This guards against post acquisition overtrading.
4/ Buy something with a personal connection to you or a family member. I mean connection very loosely. It could mean:

a/ The company engages in a hobby interest of yours,
b/ The company is involved in some industry you have worked in, in the past.
c/ The company supplies critical components to another one of your investments.

All these 'links' mean it won't be chore keeping up with your investments in the future.

5/ Buy shares in a company, from where you or a family member can imagine being a customer. This helps preserve your own moral investment integrity.

SNOOPY