Hi,
You could start by saying how you communicate with different age groups ie you wouldnt talk to a baby the same way you would talk to an older child. If you have a child in your setting that has communication difficulties ie has a stammer then you would give the child time to explain what he/she wants or what they want to tell you, dont hurry them or try to finish words for them and it would be good if you can go to a quiet area so they are free from interuptions.
I am doing my placement in a creche and we have ESOL families, children who dont have english as a first language and I often draw pictures of basic things like house, car etc. Makaton sign language is often used as well with babies and children especially if they dont talk it is another form of communication. Another way of communication is having pictures, photographs or symbols. The parents are the best people to talk to, you can find out alot about the child and how they communicate with him/her as they will know what works best for their child.
Avoid distractions if possible, get down to the child's level and give eye contact. Make sure you give the child time to answer you.
I hope this is a little help