I wouldn't practice against bots man, you will get much better experience with real players (although usign bots to learn the basics of comming isnt a bad idea). Anyhow just remember the key things of commanding.
1. Be adaptable with what you do, dont keep your mind set on doing something if it looks like it isnt going to work, try something else.
2. Cap as many nodes as you can hold (usually you start from the oposite side of the map that the aliens start on)
3. Have your pressure team, and your node team
4. Always have something upgrading, if your arms lab is just sitting there, thats not good (always get upgrades as soon as possible and as fast as possible) A thing is see a lot of pub comms do wrong is they lock down hives and turret them off but never get upgrades. The arms lab NEEDS to be a priority, here is the logic behind it, if you take more hits to kill and do more damage with your bullets its easier to hold your ground as marines right? Well there you go.
5. Phases are good on larger maps, put them at choke points.
6. Tf's in base = bad, electrified nodes = bad
7. Dont be afraid to use mines to guard base
8. By far what makes or breaks a commander, is how you pay attention to your marines and communicate with them, be clear and decisive. And be SURE to med your marines and give them ammo as needed. It gives them confidence if you give them meds during a fight, and also keeps them alive

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A handy little tip for medding marines, highlight them so you can see their hp easier and keep track of who needs to be medded.
Hope that helps some.