In order to kill demodex, and excellent remedy is neem oil. Neem oil is widely available in all health food stores. You will find that it has a very peculiar aroma, which I find to be somewhat pleasant. I would mix the neem oil with coconut oil and apply it to you skin.
After doing this, you may experience a die off reaction which results when the demodex mites die and their bodies liquify inside the pore. The proteins in the mites' bodies can trigger an allergic reaction which creates inflammation. Inside the mites body are staphylococcus bacterium and when the inflammation occurs a white pus filled pimple can result.
I like to treat these with tea tree oil as it is an excellent antimicrobial as well as an antiinflammatory compound. It is safe to apply directly to the skin, but it can be somewhat drying.
The second part of the equation will be to open up the pore surface. I like to use a sauna for this purpose as it can really get the sweat to flow. As this happens, the sebum will be washed away and over time, your skin will really clear up nicely. If a sauna is not available, a nice hot and steamy towel should provide the moist heat that will be useful in opening up the pores, but this will take a lot more work because the temperature will drop rapidly and you will want to be sure not to burn yourself if the towels are too hot.
I hope this is helpful and I wish you All the Best,