I don't have kids of my own (yet!) but I work with them and something I know is that there is a period between 2 1/2 - 5-ish when kids can put their shoes on (well, non-lace up ones) but can't always tell the difference between the right and left shoes.
There is a great tip to help them put their shoes on the right feet without an adult helping. Paint the toenails on their right foot in one colour and then paint a dot inside all the right shoes with the same colour. Then repeat the process with a different colour for the left toenails and shoes. This way the child can match their toenail colour with the colour in the correct shoe.
If you don't want your child wearing nail polish or you have a boy, you can use permanent marker to draw a different picture on the bottom of each foot (such as a star and a smiley face, or a simple L and R) and draw the same picture in the corresponding shoes.
It's simple but really works! It gives children a sense of independence without sore feet.
For other tips head over to Rocks in my dryer.