I am a contractor so I don't like to be too "showy" with what I wear but still like to dress well. I worked in various sectors (tech, commercial, government,etc) and depending on the dress code of what others wear. I used to wear my 3 piece Tom Ford in my previous work place. For the current work I am wearing jeans and a shirt sometime with my Common Projects.

I am not a big fan of colour socks, purely as I have stated I don't really like colours and I think is more of a "British/English style" to wear quirky coloured socks - I am a Kiwi :-)

With pocket square I just stick to white. For handkerchiefs I tend to stay with black and white, I have two main silk ones that I use. One is off white with dark navy hand rolled pipping and the other is black with white pipping.

Most of the time I am actually more interested in the fabric finish of a suit and a shirt rather than the colour (again very black/grey, navy, blue and white). For example I have a navy birdseye TF suit and I have a plain Navy TF suit, similar approach with shirts where I have normal white shirt and some checks and weaved shirts.

I suggest you go to styleforum and sartorialist to get inspired for your personal style. Sometime in my opinion I like to be subtly overdressed rather than wearing some accessories to bling up my look - e.g. a waistcoat immediately add some punch to your presentation without being too "showy" in my opinion.