There are various ways of releasing pressure from within the ears quite easily and effectively. However, a word of caution before you begin is essential. If you have been suffering from the problem of blocked ears for more than a week, you are advised to show this to a doctor instead of trying to treat it yourself. The reason for this is quite plain. If there is water blockage or something else that is trapped in your ears, then it could lead to fermentation or rot and ultimately, it could also land up causing an infection. Instead of taking the problem to this level of aggravation, you are better off seeking medical help. However, if you have had the problem for only a short while, then you can try and take care of it at home. One of the best tried and tested methods used opening up closed ears is swallowing. Take huge gulps of water and this will in all likelihood open your ears up with a popping sound. The reflex action of swallowing works towards the ear canal and help to equalize and normalize pressure there. You can also try the simple method of closing your nose with your fingers and try to exhale. As a result of this too, there will be pressure which will push the air bubble or whatever is causing the blockage to travel outwards, thus opening the ear up.
If your ears are blocked due to swimming, then it is possible that there is a combination of water as well as air pressure that has caused the blockage. One of the most effective ways of removing water and bubbles from your ears is to stand on the leg which is on the same side as the blocked ear and hop about a bit. This will cause the bubble to burst open due to the jerks and shocks that travel all the way up to the body. While this usually works very well, please do remember that it is not always successful at one go. You may need to try it a few times before you can see success. While there are remedial measures that can help to remove the blockage, there is also the list of things you should not do. Please remember never to attempt to dig into your ear with any sharp object in the hope that the water or air bubble will rupture. This might result in an irreversible damage.