Potty training in two weeks (aka 3 days)
Follow these five key points and good luck!
(reward YOURSELF at the end of the first three days so you don't kill anyone)
1: Go straight to underwear, be prepared for accidents, it is a fact of life. Pull-ups and the like are really designed to drag out potty training and cost you more money. They do not work.
2: Take to the potty every 30-60 minutes for 1-2 days and have child stay until something happens.
3: Reward system. This can be a sticker, getting a toy from a bag or a treat. We did toys for our first two children, but by the time #4 wanted to go potty, we had enough toys... so chocolate chips (semi-sweet, no dyes or junk like candybars... so if you pick something edible, make it small because you will be giving A LOT the first couple days.) Do NOT give the reward until after it happens, otherwise that is called a bribe and the child will expect it much too often without working for it.
4: Tough love. Many people stop potty training because you feel like making them sit on the potty when they don't want to is abuse or you find their stubborn attitude as a sign that they aren't ready. Well... it definitely isn't pleasant for either of you. There will come a point for most children were this scene will happen. They will be tired and impatient, they will tense up and not allow themselves to pee or poop. You, too, will be frustrated and might lose patience. Try to read, watch clips on a device or sing songs. Don't feel bad if there is 1-2 hours where it is a battle to get something to happen. LUCKILY, that one instance usually breaks a barrier and the child finally understands, "the quicker I go potty, the quicker I get OFF and get my reward!" Every time they get off the potty before "going," just sit them back on. Try to not be too rough, but look serious and repeat things like, "pee pee first," or "you need to go potty..."
5: When accidents happen... ROLE PLAY! Say "uh-oh!" have the child feel the wet underwear, try to get them to say "uh-oh" then go to the potty anyway, they usually can get a little more out. Do not punish or reprimand when they have an accident. Grown adults still have accidents when they are caught unprepared (or encounter bladder control issues) so give the little human a break. Don't make them think it is awesome, but treat the situation as "darn, let's avoid that next time," instead of the child as being "bad, gross or yucky." Practice by looking surprised and say "Oh! I need to go potty!" Then run to the potty and sit on it and say, "yay potty!" I know this sounds silly, but believe me, you will act like a weirdo doing what it takes to get this over with.
Have vinegar in a spray bottle and a bunch of washed towels to begin with no loads of laundry in line to be washed. This will make accidents easier for you mentally, absorb it up, spray with vinegar, absorb again - throw it all in the laundry.
The hardest part is over in 2-3 days maximum. As mentioned, the child will have learned by then to stay relaxed and just go. CHEER/give fives/clap/whatever every time! Just recently, I finished potty training #4 in my family, I also potty trained two children I babysat. If you dig your heels in and don't look back, your child will be fully potty trained in 2-3 weeks max. Won't that be GREAT!?
I personally have gone straight to underwear day AND night with all my children except #4. We are letting her have a diaper at night since she is not ready for a "big girl bed." That is just cruel to put her in a crib she can't get out of and expect her to hold it. I tried converting her crib and she freaked out, so not happening yet. :)
Ages my children were when we trained: 3.5, 20 months, 2.5 and 21 months. I do it when they show signs they are ready. Almost every child will 'strip' at some point, but if they strip right before or after they pee - that is a sign. If they beg to go on the toilet, that is a sign. If they grab their diaper every time they pee and/or poop, that is a sign. I personally love when they can speak the words, "pee pee," "poo poo," "potty," and "go." I also think it is great if they can pull down and put on their own pants and underwear. Prepare to help wipe #2 for 1-2 years if they potty train young. Feel free to comment or ask questions on anything I missed.