One possible version:
Good morning, dear friends. Welcome to our school. Now please allow me to introduce you to some
of our school rules. As high school students, firstly, we are expected to be neatly dressed when at school. Secondly, we should never be late for class or leave school early before it is over. The school is a place
where we live and study, so we must keep it clean. Lastly, when you are on the road, please remember to keep to the right, and, if you want to cycle to school, you should have a permit.
Thanks