Some children have a physical problem that is causing their language delay, while for others, it is emotional. Was your child once mocked by an older sibling? Do you speak a different language at home than your child does in school? Investigate a possible underlying cause and cater to your child through that specific problem. For example, a language barrier can be solved by focusing on one language at a time to avoid confusion, while a physical problem should be dealt with through a speech therapist.
Some children are shy or feel pressured to speak, so back away if you have previously been pushy. Don't make a big deal out of rare sentences or new words because this may scare your child back into being quiet. React calmly and matter-of-factly to new words and coax your child into speech in quiet, subtle ways.
Engage your child in a conversation when no one else is around and in a non-forceful way. For example, don't make a treat conditional on talking, such as "You can have this cookie if you ask for it." Rather, give your child the cookie and make him feel comfortable and then ask him what he is coloring or playing with.
Give your child the opportunity to talk by asking for specific descriptions and answers. Ask your child to tell you what he sees out the window or ask his advice on what you should do that afternoon. Giving your child the chance to speak and making him feel important can encourage lengthy answers.
Give your child toys and games that he is interested in and use these as tools to encourage conversation. Get down and play with him and see if he will talk using the game as a medium to get him started. Some children who don't like to express their own opinions or thoughts will do so through the mask of a toy character.