It's something you should incorporate in your game; if not, you could still be profitable, but you're missing out on some "value".
You can't just assume all 1/2 or 1/3 players play the same. Everyone is different. You have to pick your spots well. Don't just do it based on singular factors like:
- The opener is loose
- You're IP
- The hand you have can't profitably call but you don't wanna fold
- You think you can fold out the initial raiser
- Your image is tight
You have to combine these factors and do it when the situation presents itself. You might make mistakes at first. THAT'S OK as long as you learn from it. Just keep trying and ask yourself important questions when it goes wrong. When it's successful, ask yourself why it you think it worked.
As you slowly incorporate light 3betting into your game, you'll get better at it and eventually instinctively know what spots are EV+, when to C-bet, etc. It takes practice, but it's ultimately making you tougher to play against.
Hope this helps, GL!