My lesson plan is for beginners and has to be about describing a person's physical appearance and I need games or activities. Ideas?

after you teach them the sentences you can have them describe you and then get a student in front of the class and then describe them. Or like the game I see something yellow except I see some one tall and the kids have to point them out. Who has long hair, who has blue eyes etc.

break into groups of two and they describe each other. first prepare and then present to the class.

break into groups of four. each group describes one from the group (3-5 min prepare first) and the other groups guess who they are describing from the group.

Or have the kids come up one by one and describe someone in the room, the others have to guess who.

There's alot of websites i can send you a list if interested.

I did some volunteer teaching at an English Camp for 12 year olds in Central Thailand.. We played Simple Simon - says touch your nose etc.. The kids had a blast - me too..

First you enlarge pictures of different people from different backgrounds, either from magazines, photos etc. You place the pictures (A4 size) face down, each student picks a picture. Give them about 8-10mins to write a short description of the person. Take back the pictures and place them all face upwards on the floor, each person reads their description and another students picks the picture described. You can ask them: How do you know, that's the right picture.
But, before all this, you have to warm up with descriptive words, for example: long hair, short hair, black, blonde, red, brunette. Complexion is either dark or fair, never use black, white, yellow , brown or red, politically incorrect and not very nice to describe a race by a colour wouldn't you say.
I have used this in the classroom. It's fun. Get as many different people/faces as possible. Good luck.