Find a speaking partner
You can practice most things alone, but to really practice speaking you need a partner. And you can find native speakers to practice with at SharedTalk, LiveMocha or Conversation Exchange (REMEMBER: Always protect your privacy online). These sites will all help you find someone who speaks English and wants to learn your native language so you can practice in tandem. You might speak 20 minutes in English and 20 minutes in your mother tongue. Your partner won’t be a teacher, but they will certainly be able to help you with vocabulary and pronunciation while also helping you get more comfortable speaking English. And if you record or take notes during your conversation exchange (remember to ask permission before recording!), you will be able to identify things that are difficult for you and find ways to improve them.
Train your accent
It is actually possible to do some speaking practice alone though, especially for accent training. Choose a speaker of English who you like, someone who you think has a good accent. Try and find some videos of this person speaking on youtube or on DVD, and take a section that’s about 30 seconds long. Listen carefully to it: pay attention to the speed, the rhythm, the intonation and the pauses. Now go to Vocaroo (or use recording software on your PC) and record yourself saying the same lines. Now listen to yourself! Compare it with the original. When you think you have a good recording, save it and play it at the same time as the original.