Classroom Management (PANIC)

Hi folks,
I'm about to commence a new position teaching ESL to 30 learner size classrooms. I've taught 8-14 size classrooms before but latterly 1-1 stuff.
What I found in the larger classrooms is that I couldn't manage particularly unruly students.

I tried:

• talking to them
• separating them from their pals
• yelling (not cool)
• removing them from the classroom

but ultimately I struggled and sometimes dreaded facing them.

I realise that:

• trying to be everyones pal isn't a model system
• setting boundaries early is (hard for me to do)
• agreeing a behaviour expectations contract can be useful
• engaging them is handy (sorry it came so late in the piece) - on this note however there are prescribed materials that will be a challenge to make more entertaining

I realise there's a plethora of information about this, but find it's a bit in the cloud and tends to lack hard practical tips. Communication can be particularly hard in an ESOL classroom.

When students just don't let up what can you (I) do?

Student details: 18-19 years old who will expect to be treated as adults; university English preparation class. Generally much less mature than their age - I taught 25 year old uni students who acted like they were 15.

Really really practical tips please :up:

Many thanks