Clean your float as soon as you’ve finished using it, otherwise any plaster or concrete left on it will set fast.
It’s a good idea to wipe down the blade and wooden handle of a magnesium float with linseed oil once a month. This will help stop the handle drying out and cracking, and also protect the blade from corrosion.
Store your float in a clean dry place. Avoid direct sunlight, which could make rubber or sponge floats perish more quickly.