Work and uniform ... ?!

Hey everyone,

I'm new here so please do forgive me if a) this is the wrong forum or sub forum and b) if this is / was discussed else where. 

I have just started to work for NAS as an adult support worker, still undergoing training etc. However clothing / uniform and the such like have been brought up a few times at training days. I have been advised to wear old clothes that doesn't matter if it's soiled or ripped. I'm ok with that, after a fashion. What I am going to do is wear black trousers and a polo shirt, unsure of colour(s) yet. This being why I am here. I was thinking of using one solid colour and sticking to it then I thought better of it, although I like the idea of being associated as being that colour. But if an unsavoury character has the same colour on I do not want the person I am working with thinking they are safe too. So I thought varying coloured shirts each day would be better. I'm going to do a 'bulk buy' of coloured shirts, but which colours would be best? 

I understand that some people are most likely sat in their chairs face palming at this but it is a genuine concern. Some people I will be working with are very sensory lead and I do not want to overwhelm them with wrong colours. Say red for example, as to me that is a colour of danger. I've read about blues / greens being 'trust worthy' colours, and purples being 'calming' colours. Any suggestions and or advice would be gratefully received! 

Also do NAS supply work tops? Can't find anything to suggest that they do. 

Thank you you all for reading and most likely thinking ... Stop being so daft ... 

Hopper