My rules with stocks or any investments are:
- Never risk money you are not willing to give away.
- As soon as you've made your investment money, pull that amount (or double if you're able) out, and put back to a safe place.
- Then feel free to risk/play/gamble with the amounts you've made over the investment as a safe way to go for that big payday while still having original money to reinvest if it drops.
Enjoy!
K