留学生在理发时，可以根据自己的需求和习惯选择合适的英语表达。以下是一些常用的英语口语：

基本需求表达

I'd like to have my hair cut.

I would like to get a haircut.

具体发型要求

How do you want it？

Just a trim, and cut the sides fairly short, but not so much at the back.

I want a short cut.

Can you make it a bob？

I'd like to get my hair straightened and trimmed.

询问发型师建议

What style do you recommend for my face shape？

Do you have any pictures of the hairstyle you think would suit me？

表达不满或特殊要求

This length is too short for me.

Can we add some layers to my hair？

感谢与告别

Thank you for your help.

Do you have any other services I can use today？

通过这些表达，留学生可以更自信地与理发师沟通，确保自己得到满意的发型服务。