Here’s something you can do if your place has a casual dress code: Business Fridays. On Fridays, wear a tie and dress shirt, wear a three-piece suit, whatever. Go as Mad Men as you can, except maybe without the drinking and smoking (unless you and your workplace is cool with that.) The important part: do this forever. This way, you’ll always have an excuse to wear a tie on Fridays.
Also, schedule job interviews on Fridays.