During the cycle, if you do a fishless cycle, don't change the water at all until you have 0 ammonia and nitrites and a large number of nitrates. Then do a 50% change. For a fish in cycle, rely on your test kit to tell you when to change it.I am getting a 10 gallon tank and I have a few questions...
How long should I cycle it?
Until the cycle has finished. Fishlessly (which I would definitely advise) it usually takes about 4-6 weeks. Using live plants or "seeding" (using already cycled media to dump good bacteria into the new tank) do speed things up.
You won't know the cycle has finished unless you test the water (use a reliable kit like the API master kit, not a strip test).
Is it alright to put my plants in it while cycling it?
Yes, put the plants in during the cycle. They'll speed things up.
Is it easier to keep nitrate levels and stuff like that normal.. I seem to be having trouble with my 2 gallon. :|
During the cycle, no, but after the cycle, it's all fine.
Would a betta, 7 neon tetras, and 2 mystery snails be too much in the tank?
Borderline. I wouldn't have the snails. They contribute nothing and poop like machines, if machines pooped. I'd also consider ember tetras instead of neons. Make sure you have a backup plan in case your betta doesn't appreciate the company, because it's never a given.
What is a good low current filter I could use?
I can't advise you on brands as I'm in Australia, so I don't know what's available. I use a baffled Fluval U1.
How many watts should the heater have?
4-5 watts per gallon. Pretty much a 50 watt heater.
If there is anything else I should know please tell me!
After the cycle, 25-50% per week is the norm.