What do Men Need to do to Dress Formal
There are no stock answers to dressing formal, as it is situational. Formal dress for a high school graduation will be different than formal dress for a black tie event. A black suit would be considered formal for a funeral, but over the top for a speaker at a local community club. Do your homework, and find out the definition of formal for the event in question.
In general, a black tie event will require a black tuxedo with all the matching accessories, no top hat. You can choose between a black belt or cummerbund. Black shoes and socks are a must. A black tie or bow tie will complete this look.
Some other formal attire requests are; white tie, semi-formal, informal, and dressy casual.
For white tie, you will add a top hat and white kid gloves to the black tuxedo. Semi-formal and informal both require a black suit and tie. Dressy casual will be nice dress pants with a sport coat or classic navy blazer.
If you can afford to do so, and your social calendar will generate many black tie invitations, consider investing in a custom made tuxedo. The fit and appearance will be your reward. Renting a tuxedo can be worse than trying to buy an off-the-rack suit. You can have the suit tailored to fit better, but may not be able to accomplish that with a rented tuxedo.