I had to share a room with a close relative (I dare not to say who as she might read this) while we were on holiday. She snores and I am a light sleeper so it was a recipe for disaster. I decided to get many different types of ear plugs to test which one actually worked on me. I know it sounds geeky. But I am sure someone out there might find this information useful as well. Here comes the ear plugs road test results!
There are 3 types of ear plugs currently in the market: foam, silicone (yes, like those used in breast implants, I think!) and wax
Foam
It is designed to be used inside the ear canal. They are generally specified according to the amount of dB it can reduce. It can be as efficient as 34dB. Users are supposed to ‘roll’ them first before putting it in. It took me a whole year to perfect the skill of ‘rolling’. Basically, this involves twisting the ear plug until it gets thinner and more elongated. Then put it straight into the ear canal. The foam expands inside the ear canal and stops the sound from going through.
If you do not complete this procedure properly, the ear plugs will fall out in your sleep as you move around. Some people, especially ladies, have small ear canals. Thus, it could be difficult for them to put the ear plugs in. There are websites like Snorestore which sell smaller ear plugs for ladies.
The pink pair above is called Dreamgirl Earplugs 30dB. The cross indentation in the middle helps the ear plug to reduce in size during the ‘rolling’ process. It fits into small ear canals. The purple pair above is called SafeSound SlimFit 29dB. It is soft and can be rolled easily. I personally use them both as sometimes I find it easier to roll the former but sometimes I find it easier to roll the latter, depending on how tired I am.
Silicone
It is designed to be used outside the ear canal. Users should roll it to a small ball (like plasticine), place it OUTSIDE their ear canal and then press to flatten it. (like sealing the entrance to stop sound from getting into the ear). 
However, when I used it for the first time, I pressed it quite hard (as I was desparate! ). The difference in air pressure made me go partially deaf the next day. It was only until late afternoon before my hearing came back. So beware!
I tried not to press it too hard since then, but it got stuck with my hair and fell out in the middle of the sleep. It is not a good material to use.
Wax
It is designed to be used outside the ear canal. It came wrapped in cotton wool. Users are supposed to remove the cotton wool and use it the same way as the silicone. However, the cotton wool got stuck on the wax and it looked disgusting. I did not want to put it anywhere near my ear at all. Yuck!
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