Though I am not yet an experienced trader, I think I can write already some general tips I find important when trading futures.  So, here it goes:

Starting Tips:

1. Before trading, make sure to take a good course and learn how to do it.  Trading is a kind of profession, not a game.  If you don’t want to lose, find a course or a mentor who will give you the basics:  How to understand the market, some useful indicators, etc.
2. Before trading on actual money, try a demo.  There are a lot of trading demos you can choose from.  Sometimes you will have to open an actual account in order to get the demo, but it is worth it.  Trade till you are confident enough.  Take you time:  it can take a few months or even a year.  Don’t skip this stage.
3. When you decide to start trading, go slowly.  In the first few days make sure you are making profit, even if it is a small one.  Then gradually upgrade your expectations.

Trading Tips:

1. Decide about your strategy:  What indicators will you use, when will you decide to enter or position or exit, how many contracts will you use.  Be disciplined: Stick to your program!
2. Give yourself limits:  Decide what is the maximum no. of positions your allow yourself, the profit you expect for each day, the maximum loss you can take for a day.  When your trading meets one of these limits, stop!  You had enough for the day.  Don’t be too greedy.
3. Don’t enter a position without fixing a stop loss.  Find a good point for your stop loss, and don’t forget to put it.  Fix the point of stop loss according to the market.  If your budget isn’t enough for this stop loss, don’t enter a position.  Putting your stop loss too close is setting yourself for losing.
4. Learn from your mistakes:  If you had lost, look for what you have done wrong and mark it down for the future.
5. Be optimistic:  Don’t trade if you have a feeling you are going to loose.

Good Luck!