However, in terms of choosing a cardigan; we have quite many options to choose from the styles and colours but here I would suggest two types of cardigans for you which is such versatile options and you could be effortlessly elegant whether you dress up or dress down.
Obviously, the cardigan is a type of knitted garment designed with an open front and it gets the name cardigan from the 7th Earl of Cardigan also known as the British Army major general James Thomas Brudenell.
The button-up sleeveless cardigan is an exuberantly stylish statement as well substantial layering piece for men's winter wardrobe collections.
Although it's substitutional for a waistcoat (if you would like to wear a three-piece suit), it keeps your tie in place also it nicely covers the waist of your trousers, on the other hand, I love about this cardigan is the colour that we could explore and experiment with our various style of outfits, but essentially the best options a navy and the shades of greys; because the versatility of this colours will always a nice compliment to your outfit.
Thereafter, you may go for some bright colours as well; orange, bottle green, purple and such, and then make sure about the length of the cardigan is supposed to fit on your waist nicely, most importantly when you wearing a button-up sleeveless cardigan underneath your suit jacket or sports jacket always unbutton the last one or two button otherwise it will create a bellow around your waist which is quite an uncomfortable.
However, for instance, the charcoal grey trousers, chambray shirt, brown knitted tie, layered with a burgundy sleeveless cardigan and a sports jacket (gub club plaid) is absolutely a remarkable look.
On the other hand, If you would like to wear a tie, try to wear silk and knitted tie and such, and never wear a bow tie with a cardigan.
Although, on the casual side, the best way to wear a sleeveless cardigan is with dark-wash denim jeans and a casual shirt, layered with a nice sleeveless cardigan and a sports jacket (gun club plaid and windowpane), or perhaps olive green corduroy trousers, chambray/ denim shirt with a navy sleeveless cardigan and brown sports jacket (tweed/ corduroy) as an optional you may go for a black or navy knitted ties.
Relatively, the shawl collar cardigan is an alternative to your sport jacket and it looks somewhere in the middle; between business casual and casual, though it's more functional and also creates a bit more relaxed and elegant look as well.
However, you could wear a shawl collar cardigan with corduroy trousers, a shirt and a knitted tie to your office as a causal Friday outfit and dark wash denim jeans, crew neck t-shirt/ polo shirt and layered with an olive green shawl collar cardigan.
On the other hand, charcoal grey odd trousers, an ice blue striped shirt with crest/ regimental tie and layered with a navy shawl collar cardigan and interms of footwear you may try a nice pair of suede chukka boots (black/ brown/ navy) click here to know more about boots for winter.