After I had been promoted to team leader in Civil Aid Service, I needed to lead a camping team which was necessary for further promotion.
I feel uneasy about this statement. When I read this, I feel that you are doing this just to get a promotion, not because you like to lead people. Maybe you could try rewriting this to accommodate your true feelings.
Or, simply, you could take out "which was ... promotion" and then combine the sentence with the second paragraph.
Before the journey, I was quite confident about my ability to lead my team well because I had done some planning and studied hard about camping.
Good. To make this better, I suggest adding a transition to the end of this sentence saying that you weren't expecting the challenges ahead. Maybe;
"... about camping. No matter how hard I studied, however, I wasn't prepared for the accidents ahead." or something similar. Do you get my idea?
Soon after we arrived at the camp site, we were ordered to build a tent where we slept .
I think this is redundant. I would assume that a tent is for sleeping... :)
Bad thingsluck came twice
I think "luck" would better serve this purpose. :]
With the help of my teammates, I used the watch-method to determine directions, and , together, we finished our task.
For the rest of our journey, weWe finished the rest of the journeyfinished it withbygood cooperationcooperating and being calm.
Now I know that when things do not go according to plan, I should notdon't panic and try to solve the situation together.
It's getting better. I see improvement in the grammar and thought organization.