What's your number one trading tip for new traders?

Updated
Giving back to the community is a great thing.
Please share some of your hard won insights to other traders.
It can be anything really - a one liner or a chart with deep analysis.

Post your tip, advice or best practice in the comments.

Cheers!
/Esper
Note
Please go here instead:
What's your number one trading tip for new traders?

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