Any suggestions on traveling Tibet?

I will visit Tibet this summer with my friend. We are now studying in Beijing, China and will to the notable" Roof of High Land" this summer vacation. We have kown that Tibet is very different to any other places in China. It is a sacred, religious place and the people, really different.   whoever once traveled there or anyone have any suggestion for us on, say, what we should bring, some cultural things-dos and don'ts  etc. and is that time ok to visit there?   we really appreciate if anyone one can give some ideas.

yes, there are somethings you should be sentive about when traveling in Tibet. [size=2][font=arial][/font][/size]  [size=2][font=arial]Tibet people are religious people and visitor may find their customs and practices are very different to that in the countries they come from. Although Tibet people are among the easiest to get along with in China but there are still some points you should be keep in your mind when you are there: [/font][/size] [font=arial][size=2]1.[/size][/font]       [font=arial][size=2]Do not photo them without permission. For religious reason, Tibet do not want their photos to be taken. [/size][/font] [font=arial][size=2]2.[/size][/font]       [font=arial][size=2]Do not talk the sensitive issues like political, religions. [/size][/font] [font=arial][size=2]3.[/size][/font]       [size=2][font=arial]Take your hat off when entering a chapel.  [/font][/size] [font=arial][size=2]4.[/size][/font]       [font=arial][size=2]Do not take photos during a prayer meeting and in some larger monastery, you may need to pay a small fee for the privilege of taking a photo. [/size][/font] [font=arial][size=2]5.[/size][/font]       [font=arial][size=2]Do not touch or remove anything in an altar. [/size][/font] [font=arial][size=2]6.[/size][/font]       [font=arial][size=2]Do not wear shots or shot shirts in a monastery and do not smoke in a monastery. [/size][/font] [font=arial][size=2]7.[/size][/font]       [font=arial][size=2]Do not eat horse, donkey and dog when in Tibet. [/size][/font] [font=arial][size=2]8.[/size][/font]       [font=arial][size=2]always circumambulate monasteries, piles of Mani stones, pagodas and other religious structures clockwise. [/size][/font]Never touch a Tibet People on the head.

and you may consider to bring thick, warm coat with you for temperature differs dramatically between daytime and night., take Lhasa, for example, could have a temperature during daytime of around 10-25 centigrade, but it can drop down to 0 or lower at night.   As the solar radiation is unusually intense, so you should bring sunscreen and sunglass, lip cream to protect your eyes and skin.