It is good to clean the car right after use, when the dirt is fresh and will come off with ease. 

Damp clay/mud is difficult to get off the plastic parts once it has dried on.

After driving, the first thing you always do is switch off the power and take off the battery. After this, you use a brush to remove any loose dirt.

If the dirt is stubborn, you can use a cloth dampened with a cleansing agent like Muc-off, or a solvent cleaner like Nitro Blaster to rub it off. 

By using a cloth, the dirt is absorbed, which keeps the working area clean.

For easier cleaning with off-road cars, it’s good to take the tyres and the rear wing off, making cleaning the suspension components significantly easier.

After cleaning, it is good to check the condition of the bearings, especially if you’ve been driving in wet/damp. 

You should oil the bearings with an appropriate type of oil to protect the bearings against rusting in the future. Something like GT85 would be perfect for this, as it has PTFE.

If, or when, you come to store the car for some time (Over winter for example), it’s good to clean the car thoroughly before. You can do this by removing the electronic components for better access when cleaning, an old tooth-brush, or paintbrush is fantastic for getting into all of the hard-to-reach places