Don't know where to start

Hi, I have a 2 year old boy, and I'm wanting to potty train him for daytime before our second is born (February). I'm not concerned about nighttime since he's so young. I just want him to get the hang of daytime. Is this possible? How did you potty train? He's been in pull ups since he was 1 (grew out of diapers lol). I've heard about "rubber pants" but not sure how that works. Or the naked method? I don't know how that would work either. He doesn't tell us when he goes pee, he will just hand me a clean diaper when he does to change him lol. He knows what the potty is and knows that we go on it, but I don't think he understands what it is other than somewhere to sit and then flush when we get up. I have sit him on the big potty (we have a little attachment seat) but he just giggles. Does a little potty training seat work better than the big toilet? Has anyone actually trained their 2 year old? I have until February so I'm not really rushing him. And if he's not potty trained then it's not a big deal either, we will try again at 3 lol.