I did simular to Lanny with mine, mine were all aged 2 and then I started , if your not sure about doing it in house, try the summer after they are 2 as easier to be naked and garden for mess etc. I actually had more trouble with one of mine , they didn't have any interest in sitting on potty and weeing, could understand that was what it was for! and so did sweets in the end (can't remember which child it was), bad mummy I know but it really kick started it and I only had to give sweets as reward for a week! they forgot about them , but that connection with reward for wee and potty had been made then.
I tried those pullup pants once , and they were rubbish , my kids couldn't feel wet and they just confused them.
I would make sure you have about 20 pairs of pants before you start, as you will never turn around the washing !!
Ive started saying poo poo several times , when Devon is clearly doing a poo, now , hes only 8 mths, but hope to start him making a connection with the words poo poo and what he is doing - may help , I'm not sure