In my experience on colour playing, navy is such such a formal colour to me but with some special characters; it even sounds like a formal colour the word itself before you look at it, but it is more mysterious than black.
And also dressing is very personal, do not try to reinvent yourself, because it will probably be unconvincing.
As it is originally short for “NAVY BLUE”, the uniform colour, so navy is always giving impression as seriousness, formal feeling to people, Plus which is also a dark colour. I think there is no better colours rather than navy for you to wear for events like important dates, such as when meeting her parents on the weekend. I think Black will be too much, a little bit sad and dark, navy is brighter, happier, slightly colourful. It looks even cooler for the warm days as well.
so here I paired the navy pants with a super cozy grey cardigan. I believe the grey and the texture of the cardigan itself can blend with the formalness off the navy pants but still not casual enough to make it look like a sunday morning off bed grabbing milk look.
Location : Sydney Cockatoo Island
Photo by : Tim Lo
And of course, here I have only introduced one of the many ways that you can dress navy. – Weekend with important people.
This kind of weekend is especially tricky, clear your mind before you looking for your car key as you may be going anywhere without forecast with this oufit: dinner at five star hotel to showoff or for a happy China Town night market hotpot, going to a zoo with her animal loving family or going to the Bondi Iceburg for a drink or salty dip.
Anyway, dont be too casual like adidas the original track sets or neither suits up.
For more information you can checkout on Mr.Porter Tutorials.
They have used a navy blazer as example for 5 different occasions:
Elegant Eccentricity
The Preppy Update
Timeless and Appropriate
Summer in the City
The Weekend Getaway