The cadets have a variety of different uniforms for different purposes.
Can anyone give some guidance to a new probationer as to what to wear when.
It goes without saying that it should be clean and tidy but are there any do’s and dont’s etc?
I am past the age to wear uniform but could get some DPM but don’t want to put any noses out of joint!
There are set circumstances laid out in the appropriate policy docs when CIs can or sometimes must wear combat uniform (ideally MTP rather than DPM): including shooting, fieldcraft with weapons, road marching, operating UAS, etc: but I think it’s forbidden at all other times. Experts in those areas will be able to comment further.
For general Sqn nights, smart casual is always a good start. Polo and cleans jeans something like that.
In the 1358 rewrite I want to include better guidance (not policy before you start all shouting at me) so there’s always a benchmark to ignore it accept. But it will formally help answer these Q’s
Shorts and CI polo in the summer. Jeans, CI polo and CI jumper in the winter! 
Yeah, my unit asked that I wear a collared shirt of some description, chinos/jeans etc and ideally smarter shoes that weren’t trainers, with a suit tucked away for the odd night where dressing up a touch smarter was appropriate (like annual formal inspection).
In my - frighteningly - more than 30 years and an SI and CI, I’ve never worn anything ‘smarter’ than jeans, t-shirt, and trainers for a normal parade/training night…
Never had a CI Polo shirt, never been asked to wear shoes/trousers/shirt, never wore a brown dust jacket thing, never wore the Jugend armband…
When I was a cadet in the ‘90s, the older ex-RAF CIs wore uniform without rank, whereas the younger ex-cadet CIs wore suits. Times change.
I’ve genuinely never seen the armband out in the wild. Do they actually exist?
They do or well did. I had an old CI who taught radio, he’d wear his armband with pride (we’re going back 10+yrs now and the CI was in his mid 70’s).
Not seen one in years, not worn anyway, last ones I saw were about four years ago when I was clearing out stores of a Sqn I was supernumerary at, to be fair, I thought I’d uncover the ark in that stores 
I don’t know you’d been in my stores!
I started as a cadet in 88 (?), and I never saw CI’s in uniform sans rank, or in suits.
It’s a Sqn thing, not a times thing.
You aren’t missing much, my CI’s used to wear a Squadron Polo as standard
What’s this summer bit? Haven’t stopped wearing shorts yet…… 
New vocation as a postman?
There’s a couple of softies around here who wear long trousers when it drops to about 15C!
Yeah, I’m aware I probably don’t have to, on my unit it was just encouraged to for anything formal and I don’t mind it - I’ll take any excuse to break out the old suit quite happily, I don’t get to dress up smart nearly often enough!
Shirt, trousers/skirt, shoes not trainers.
I’d say jeans are ok if clean and tidy.
Outdoor kit for outdoor lessons.
I’m not a fan of the CI polo in all honesty.
But I’m also more interested in the quality of the lesson than the instructor’s attire.
It seems as if there is a pale blue polo shirt and a navy sweat shirt with Civilian Instructor on the sleeves with RAF AIR CADETS and motto over the heart on each
Indeed, but as CIs are by definition not uniformed they can’t be compelled to wear it. I always wore a regimental polo shirt or tie (with a shirt, obviously) instead.
Just because they aren’t uniformed doesn’t mean the organisation can’t set a dress code.