WJEC descriptive writing task

I'm going to be writing a description of a place or scene as part of my GCSE English Language course work and i'm really struggling with how to plan it and write it.
We have to literally just describe the scene. No characters, we have to avoid making it into a story.

(I did it once with the scene entering a music venue, but I didn't get the grade I needed so my teacher has asked me to re do it. which means I have to use a different task brief.)
I've chosen to do the scene at a busy airport terminal because its the only one on the list I've been to recently.

Can anyone give me ideas, tips, advice on how I should go about this task.
Descriptive writing isn't something I'm particularly good at.