Here's the method I used, and it worked like a charm! Just do it with a fun attitude, making a game of it so that your child will relax.
Go to the store and buy a box of "Nerds" candy. Back at home, have your child dump out the Nerds into a large baking pan or platter and then sort them into piles by size. (The candies range from miniscule dots to clumps as big as capsules.) Get a big glass of water and show your child how to put the tiniest Nerd in her mouth, take a sip of the water, and swallow without chewing. Once she can do it with the tiniest one, move up to the next size and try again. Continue doing this until she has worked her way up to the biggest Nerd of all. If she can swallow the biggest size, she's ready to swallow pills as well.
I wouldn't recommend swallowing an entire box of Nerds whole, as that might result in a tummy ache. But she will probably only need to do this 5 or 6 times until she has worked up to the biggest, and that small of a quantity shouldn't cause any problems (unless she's allergic or something). Good luck!