If you live in any metropolitan area, chances are you will be lucky enough to meet native speakers of your target language. Take advantage of this opportunity. I tend to be shy when I am speaking another language. It can be difficult breaking through that barrier, but trust me it will be worth the effort.
Start with the right attitude. If you have the right attitude the experience will be pleasurable. Native speakers tend to be happy that you are trying to speak their language. They can be very encouraging.
1. Be flexible about their correction of your pronunciation or grammar. I stopped worrying about making mistakes a long time ago. Enjoy yourself, and be grateful for their corrections. Smile and show that you are happy they corrected you.
2. There are some phrases you must master before speaking to a native. This includes greetings, presentation of self, how and why you learn the language.
3. Speak gently, look at them straight in the eyes and listen carefully to what they say.
4. Talk to people gently, looking them in the eyes and listening to what they say. Some people may not feel like talking.
If someone answers you in English or in another language when you spoke in your target language in the first place, do not go on in the target language as if nothing happened. The other person is making efforts to be helpful by talking to you in English, or just want to show off its skills (very common in some countries like Switzerland and Germany). So if you want him to help you with your target language, you have to acknowledge the fact that he speaks English, congratulate him for his English and then explain that you came here to practice this beautiful language that is your target language.
5. When you hear a word you don't understand, wait for the speaker to finish his phrase and then raise your hand with a smile and say Excuse me Sir but I did not understand the word XXX ? What does it mean ? Would you write it down for me ? , preferably in your target language, and hand them a blank flash card. Of course a beginner cannot do that because people would not have enough time to teach him everything. But still they will almost always be willing to help for a few words. When I traveled I made my own dictionary of words that I learned along the way.