Take a clean old rag and clean off all particles from the blades of the skates. Clean off any mud deposits so that you can have a good look. Mark the areas which have developed rust.
Rub steel wool over the rust areas. The steel wool will get rid of light rust and prevent it from building up. However, do not apply too much pressure on the wool because the steel can scrape away the blade and harm its balance which will effect your play when you wear them.
Lemon is known for its anti rust properties because of the citric acid in it. Roll a lemon on a flat surface under your palm like the counter or table. This will soften it up and easier to squeeze the juice out. Squeeze a fresh lemon into a bowl. Dip a clean cloth into it. Now use the cloth to clean the rust. The whole rust area should be well coated with lemon juice. Let the lemon on for a couple of minutes before you clean it off.
After the lemon treatment, rub the steel wool over the surface again. The lemon should soften up the rust which you will remove with the wool. Again, be gentle and slow at this work. Take your time to remove all the rust.
If these home remedies do not work, take your blades to a professional blade sharpener. He will sharpen your blades without harming their balance through a grinding wheel. The process will get rid of all the rust on the surface and also improve the performance of your skates.