What basic knowledge should I know before forex trading?

1. Find out how the forex market works.
2. Learn technical analysis.
3. Get a trading platform and find out how to operate.
4. Find out risk involved in trading and work out your own risk management.
5. Combine steps 1–4 above and apply to a demo trading environment.
6. Continue step number 5 until you feel ready to take on live trading. Once you are ready, go to live trading but start your trading at only 5% positive size of what you expect to do. This is because live trading can be frightening; many individuals fail to overcome their fear while others make fatal mistakes that wipe out their trading capital when they take their baby steps.
7. If you go past step 6, upsize in small increments while constantly checking your performance, verifying that you have gotten steps 1–4 correctly.
8. Constantly check your psychology. If you reach a point you are not sleeping peacefully at night or if you are nervous, cranky, angry etc. or if you are glued to your terminal or rejecting social contact, you may either over-trading or your psychology may be in bad shape.

If you can get steps 1–8 correctly you should be fine. Give it time, don’t be surprised that this process (especially step 8) could take many months, even years for you to become totally comfortable.

You want to make money in a sustainable way so that it becomes a career/lifestyle, not a-flash-in-the-pan-brilliance built on shaky foundation.