This combination of a turtleneck and black jeans is solid proof that a safe casual outfit doesn't have to be boring. You could perhaps get a little creative in the shoe department and introduce a pair of chelsea boots to the mix. Keep this ensemble in your front hall closet when warmer days are here, and rest assured, you'll save time trying to pick out what to wear on more than one morning. This pairing illustrates how to stay fashionable as you get into your 30s.