re: Poker & Some tips on working out how much to bet / raise etc.
are a consideration; making it so that your opponent is making a mistake to chase if they have a flush draw for example.
But the main considerations are your opponents and your hand. That is to say, if you're playing $10nl or lower and your opponents don't pay attention to bet sizes, then bet bigger with a big hand, as much as you think your opponent will call. If it's a continuation bet with only one overcard or a hand without a lot of value, bet 1/2 pot or as little as might get them to fold, unless they never fold in which case there's no point betting.