Washing your tube and earmold is only necessary if it is plugged with wax or debris. When the tubes start to harden you should bring it to your local clinic to have it replaced.
Examine the device for debris and remove it with a soft brush or a dry cloth.
Remove the earmold from the hook to clean it. Some earmolds, especially those made from soft materials, can become discolored and stain over time.
Soaking the earmolds in warm, soapy water once each week will help. Allow them to completely dry overnight before use, and do not use alcohol or other harsh chemicals on them.
Use a bulb blower to force water out of the tubing and then allow it to dry overnight.
The tubing in the earmold should be replaced when it becomes yellow or stiff. This is done by your hearing care professional.
(2) & (3)