Dear Peter，
I'm glad to receive your email. As it is required，you are supposed to hand in the poster before next Friday.
Being your close friend，I am extremely willing to share some ideas about designing the poster with you.First and foremost，the basic safety rules are of great importance，which should be included in your poster.In the second place，following the safety rules is so meaningful and crucial that you had better remind your readers of its significance and advise them to be careful both in and out of school.Last but by no means least，if I were you，I would add a few suggestions about safety awareness，considering that better safe than sorry.In addition，it is a good idea for you to draw a few pictures on your poster so as to make it more lively and acceptable.
If there is anything more that I can help with， please let me know.
Yours，
Li Hua