The point of pocket squares is that it doesnt really need to match with anything. matching a pocket square to a tie, is seen as perhaps a tad inellegant and the domain of gifts sets from NEXT or TESCO. In a pocket square its a good idea to find something that in its initial colouring or patterning, doesnt really echo anything else you're wearing, but has perhaps an accent colour or tone in it that is picked up somewhere else in your outfit. It could be a small sub colour in the tie, a weave in your shirt or even a fleck of colour in a pair of glasses. I guess what I'm saying is, just pick a material that has a different texture to your suit (probably a smooth silk) in a pattern that doesnt mirror anything else you're wearing. perhaps a paisley.
I do understand the pocket square etiquette I was only asking for some suggestions from the guys not a lesson on how to match things (or not as the case may be) but thanks for the input. I am still leaning towards the paisley.
Burgundy sounds good, especially if finances run to the Grenadine tie, less expensive option being a knitted version. I'm another one who'd stick to a plain coloured tie and if you fancy a paisley pattern pocket hankie be bold and go for a really positive one.
PoW suit always looks so classy to me.
You may also want to look to the color of your shirt or socks for a pocket square match. There is also various theories on color and what feelings/meanings you want to communicate(red dominance; blue cooperation etc).
Matching tie and square, generally a no; but there was a significance for that too.
I'd just go with the tie.
There's just so many meaning to color and side and pocket with sqs and bandanas and hankies best to go without.