How to clean my MacBook Pro 13 inch???

—> How to clean your Apple products. 

If you don't want your MacBook Pro to get dirty, use a brush to clean off the dusts that stick on your keyboard, use a cloth to clean the MacBook's screen (I recommend you to use smooth cloth to avoid accidental scratches)

You should clean your Mac weekly (or daily) to make it clean and functions normally. (in some cases, dusts can go into your speakers, which results make the audio quality worse, or for MacBook Pro models that have the Butterfly keyboard, too much dusts can make some keys unable to press.)

Hope this answer helps you.