How can I improve my speaking skills?

The best way is simply to practice. If a student is uncomfortable speaking French to (or, indeed, at) their friends and family, they could just spend a few minutes, before getting up in the morning, to say aloud some mundane sentences about what they will be doing later that day. Likewise, before going to sleep they could relate some of the things they have done. This is a great technique for spontaneously forming sentences in the past and future tenses.