假如你是李华，你在美国的朋友Mandy给你写了一封信征求意见。请根据这封信的内容给他回一封信。
Hi Li Hua，
As an ordinary middle school student，I plan to study abroad some day，but when is the proper time，before or after graduation from college？And what should I prepare before I go abroad?
Best wishes.
Mandy
