Here is how to be a good lyer. This requires only one thing: patience. I will give you the steps plain and simple, and you can read further in the book to further understand one step in particular:
Step 1: Find something to lie about (this must be small, nothing major)
Step 2: lie about it in a painfully obvious way
Step 3: create one key thing that the person detects when you lie poorly, like scratching the back of your head or rubbing your eyes
Step 4: continue this over time until the people around you start to notice step 3
Step 5: Lie about what you want to convince them of, have supporting evidence (or good improv skills) and look them straight in the eyes with a relaxed but stern posture. All of this together will create a strong sense that you are telling the truth.