There is often much controversy surrounding hydrogen peroxide as a treatment for various ailments. One of the more common theories is that putting a few drops in your ear can help remove earwax, but some people even claim that this can also be done to help cure a cold.
If attempting this method, it is recommended that you never use anything stronger than 3% hydrogen peroxide (the kind commonly found in supermarkets), and many people even recommend diluting it with a bit of water (perhaps 50/50).
Pour a bit of the hydrogen peroxide into the cap of the bottle, dilute with water if you wish, and then using a Q-Tip or an eyedropper place a few drops into your ear and tilt your head to the side. You will likely hear some fizzing, which is normal. After a few minutes when the fizzing has stopped, drain your ear and then repeat on the other side.
It is not recommended to try this if you have a punctured eardrum, and as always, check with your doctor before doing this.