I was a Year 7 tutor in the year before this one, then took my group on into Year 8, which we have just finished.
I was very strict in Year 7. We have a bell at 09:15 which means students can enter the school building, go to their lockers and the toilets and enter their tutor rooms. At 09:25 there is a second bell and when this goes the students must be sat down in their tutor rooms and tutor time begins. Unfortunately, where our Year 7 lockers and tutor rooms were, the bell could not be head. So, even though I wanted to have 10 more minutes to prepare for the day ahead, I used to go to the lockers at 09:15 and announce "the first bell has gone", you have 10 minutes until tutor time. Then I would sit in the tutor room and invariably deal with queries about lost property or just have a chance to chat sociably with those who came and sat down before 09:25. At 09:25 I would call them in to the tutor room if they weren´t there already.
I kept on top of lateness, uniform infractions, forgotten planner, etc. with a breaktime detention for the first offence, a lunchtime detention for the second and then referred upwards to the co-ordinator.
We kept to a timetable for tutor time with Monday being planner check, Tuesday House assembly, Wednesday key stage assembly, Thursday PSHE and Friday silent reading. In tutor time they were allowed to sit where they wished (with the threat of a seating plan if they could not listen quietly) and had to be seated with bags on the floor and listening quietly where necessary. Also no doing homework during tutor time.
It was hard work and I did envy the tutors who just sat at their desk drinking coffee whilst World War 3 went on around them, but this past year, Year 8, has been so easy. They knew all of the "rules" and just got on with it.
At the same time, we have had lots of fun doing House or charity activities together, I bring in sweets once or twice a term, usually after a period of exams. I try to come and watch them when they are participating in activities at lunchtimes, and organise PSHE topics and activities that I hope they will find interesting and enjoyable. Each month I run a tally of housepoints and reward those who have achieved the highest totals in the tutor group.
Sorry for the long post. Basically by being consistent, and strict, in Year 7, I hope I have built a good foundation for the tutor group in the future and our relationship also seems to be strong and positive. It is hard to go backwards and implement rules retrospectively. Year 7s are basically a blank canvas and it is up to the tutor to guide them in the right direction; yes, of course, they will want to rebel when they´re a little older, but they can get a good foundation in their first year or two and get into healthy habits.