Okay, my answer is going to be a bit different than the others. When my girls were 2, I began expecting them to help clean up. I was very strict and got a lot of slack for it from my mother. I explained to her that I am raising my daughters to be self sufficient, productive members of society. I tried a bunch of things, but when they were old enough to associate with pictures and words, I began a chart. Each day, after they did their "chores", they could move the picture/phrase over to the "Finished" side and put a cut out letter (one for each day of the week, in two different colors to distinguish between each child) in the "Chore Jar" that we created one day. I let them help me decorate the chart and jar so they would be excited about it. They had to complete ALL their chores satisfactorily to put their letter into the jar at the end of the day. No exceptions.
We would make sure to make a big deal about it each night and give them lots of positive feedback so they knew they were doing a good job. When they didn't do well, we explained to them (at first through their tears, later through a few fits) that we were sorry that they didn't take care of their responsibilities and hoped that they would do better the next day. We didn't "reward" them specifically at that time because, in my humble opinion, you shouldn't be rewarded to do basic tasks. That's not how the real world works, and I didn't want them to get confused with "bribes" or material "rewards". However, we did encourage them with lots of words, hugs and love.
By the time they were 7 or 8, they wanted to earn money and began telling us about other kids at school who had allowances for things like making their bed, putting their dishes in the sink, brushing their teeth and so on. I explained to them that I would not pay them to do things they were supposed to do, and of course they thought this was completely unfair of me. I told them that I would gladly pay them to do some extra chores that were above and beyond my daily expectations. I didn't give them a list, though. I waited until they came to me with their ideas and when they had a reasonable one, I discussed with them what the "job description" would entail, what would be required of them to earn the money, and what the "job" paid. When they received their pay, I taught them to save half of their money and let them go with me every "pay day" to deposit their money into their savings accounts. Again, we made a big deal about watching their money grow and giving them lots of praise for a job well done. We also were very honest with them and told them when they didn't do so well and showed them the proper way. The other half of their money could be spent any way that they wanted, but they were responsible for it. If they lost it, that was their problem, not mine. Pretty soon they were so excited to see their savings grow, they put more than the required 50% into their accounts.
As they got older, their daily responsibilities grew. They are 14 now, and I haven't had to ask my daughters once to clean their room, make their beds, put their dirty clothes away, wash a dish, etc. They just do it automatically. By the time they leave for school, their room is clean and before they go to bed it is clean. The same people who gave me a hard time have been complimenting me since my girls were in 1st grade for how well behaved they are, how responsible they are, etc. This has also influenced them in every other aspect of their lives, too. We have taught them personal accountability since day one. It wasn't always easy, but the headaches were worth it because now we are smooth sailing. I don't have the stress of arguing, nagging or any of the other stuff. It's one of the best things I have done for my sanity, and even better for my girls futures. Obviously, every child is different and what works for me may not work for you. However, I highly recommend using this as an opportunity to teach them some very valuable and necessary life lessons. My Mom didn't do any of this sort of stuff. She argued, bargained, begged, bribed and was always easily pushed over by my two brothers and I. Don't get me wrong, she is an amazing mother, but she never taught us how to live in the real world. I got lucky and the military taught me what she didn't. My 38 year old brother still lives at home (with his wife) and my Mom still takes care of him. He and his wife "mooch" off of my parents and to this day she still makes excuses for him and doesn't see the error of her ways as she continues to enable him and his wife.
Good luck with whatever you do and remember to focus on the big picture! It's our job to arm our children with the tools to be successful, responsible, hard working, honest and productive adults(among all the other things)! Stay strong and don't give in! You'll be glad you stuck to your guns...trust me:)