When you purchase access to a private proxy or you find a suitable open proxy listed on a proxy list (e.g. SamAir.ru, Proxy 4 Free, Anon List), you need to know how to set up your browser to use that proxy. I have explained how to do this in several posts listed below.
Now, I have found 2 videos that show step-by-step how to setup your browser to use a certain proxy.
Video: How to set up Firefox to use a proxy
Video: How to set up Internet Explorer to use a proxy
