请各位英语大师帮小弟修改这篇英语作文（Jimmy写一封信邀请Penny周六去露营）.本人英语水平太低.

请各位英语大师帮小弟修改这篇英语作文（Jimmy写一封信邀请Penny周六去露营）.本人英语水平太低.
Dear Penny:
If you are free on saturday we will go to the camp.I hope you go to the gate of the school on saturday.at the same time I hope will have MP3 and umbrella with heavy clothes and sports shoes,not heavy skirt too.I hope you could have sandwich and drink coffic.in addition to this we hope us will on foot mountaineer.
Jimmy
18/July/2012

Dear Penny:
If you are free on saturday,we would like to invite you to go camping. We make a decision to meet at the gate of the school on saturday.So if you want to come,ensure you ca arrive there on time.At the same time, I suggest you have MP3 and umbrella with you,Heavy clothes and sports shoes included.But don't take heavy skirt.I advise you to have sandwich and drink coffee.In addition to this, we plan to go hiking,please make preparations for it.
yours,
jimmy

文义有些不通,hope 要加 to do,不要总重复一种句式.
修改版在上面,请过目