Good writers use words that appeal to some or all the 5 senses to help describe the topic. Here is a list of senses and examples of what they can describe. Add examples of your own under example 2 before you proceed to picture description.
Below is the picture you need to describe (post your description in comments). When you are describing pictures, use these expressions to explain precisely what / who you are referring to.
The woman ... on the right / left / in the center of the picture; ... in the background / foreground ...
Remember you can also use might be / may be / could be for speculating as well as looks, looks as if/like, etc. Use the body language of the people in the picture to help you.