Rub the sides and back of the silicone phone cover with fine-grit sandpaper. Work in small sections until the entire outside surface area has been sanded. You do not need to sand the inside of the case.
Also question is, are silicone phone cases sticky?
The reason for the stickiness is that all pure silicones are liquids. The fillers added to the silicones (silica, iron oxide, etc) make it behave like a solid, but the sticky liquid is still there.
Then, can you paint your phone case with nail polish?
How can I make my phone case less slippery?
How can I make my phone case more protective?
For a baseline level of protection, choose a case made of a shock-absorbent material (like silicone or rubber) that covers your phone’s vulnerable corners. Shoman advises smartphone owners against plastic cases, which do not effectively absorb shock and are likelier to translate the impact onto the device itself.
Why is my phone case slippery?
When looking at why some phone cases are slippery and ours aren’t, the main reason is the material we use. For example, many lesser cases are made with a range of plastic types. While these materials are affordable and easy to make, they have very little to offer in the form of grip.