Timing your visit to the hair salon

Use salons that take bookings and/or avoid salon busy times whenever possible. Especially late nights and Saturdays.
Take the first appointment of the day, it's the backlog of clients prior to you that will cause your hairdresser to run late later. Now the only people you have to worry about are you and your hairdresser getting out of bed on time.
If going in later, call first to check that the appointments are running to schedule. At least then you can stay in your office and work or grab a sandwich on the way.
Confer with your hairdresser to take the appointment straight after their lunch. As a hairdresser normally uses this time to catch up!
Ask your hairdresser as you book your next appointment, whether the person booked prior to you normally runs on time. Some people are always late and your hairdresser will know this.
Ask when you book how long it will take so you can plan when to pick up the kids, husband or lover or whoever.
Let the person doing your hair know that you expect to be out by a certain time and check that this is right before they begin. Either one of you can make a plan at this point but 5 min before you have to be somewhere is too late.
If you are having a colour or perm, when quoted a time frame, double check that means the time when you will be totally finished. It is a common mistake of hairdressers to quote times that relate to how long it takes them to do the work rather than how long the whole thing takes with processing and rinsing times included.
As a rule of thumb, always allow an extra half-hour!