Pale blue candy stripe
Cashmere gun club check
Raw denim (2 and a half years wear)
Snuff suede chukkas
I'm not saying I do it well or right, but I do this on occasion.
2 things I quickly learned are no tie (the tie, to me, brings the upper body to a level of formality that is not congruent with the denim) and not baggy jeans.
It seems obvious to me that your shirt should be tucked in and under no circumstances should you be wearing something that could be described as a "tee shirt" underneath.
I think jeans and a jacket/sportcoat/blazer is especially tricky because you have to so closely watch the levels of formality involved, which are "naturally" at odds with each other. It is very easy for this look to turn into a trainwreck.
You can do a knit tie, works quite well, just need to make sure you loosen the collar and no spreads. Shirt tucked in = always. T and jacket can work if highly textured and you're in shape. T should be very fitted and not long. Excuse the color of the photo, distorted heavily by iphone. This was a look I posted on the main forum and actually got some compliments on. Not for everyone but was pretty well liked on the street. Jacket = linen, t = highly textured. It's a gray blend against a blue jacket, which I paired with a slim pair if white denim and some brown loafers. Again the colors are distorted.
The high low concept is not tricky imo, you just need proper texture, fit and and understanding of how to go high and low with regard to the items you choose. Denim and a coat can be a staple look and if done right very sharp indeed.