Hello I am new to cash tournaments at 22 years old, and I am looking for round table tips. I have only played 3 tournaments live as far.

How do you get early reads on players you never played with before, what do you look out for?
At which level would you increase aggression?
Whats the best strategy at 10-20 big blinds or less without going all in?
Any tournament, round table tips and strategies appreciated.
Cheers,
Victor
Dublin, Ireland