What is it you are uncertain of?
There is no such thing as a wrong mind map. If you start worrying that you are doing something wrong then that will hold you back. Just churn stuff out and chuck it on the map.
Start with the topic you are mapping in the middle. Then anything that comes to mind about the topic, write it down and draw a line between it and the central topic. Then repeat with the new "node". Don't hold back on anything.
If you feel that nodes that are on opposite sides of the page should be connected, don't worry about it, just draw a big line connecting them... It doesn't matter if any of the connecting lines cross over.
Think of yourself as a crazy artist. It may help to be as creative as you can with the ideas. Use different colours for each branch.. draw pictures.
Go crazy and don't hold back!
When you feel you have fully dumped your brain you may be left with a huge mess, but there are probably some excellent ideas that have come out. If you want to can then copy that into a new, neater map. The process of doing that may bring new insights which may prompt you to create another map, and so forth!