Optics
Being a consultant is not just about the work you do. How you are perceived is a big part of your job. This is where consulting differs from just having an industry job. Consultants will need to work hard to be perceived as a hard-working expert. Once you finally achieve that goal, the project will end and you will roll off on to another project where the process will begin again.
Coming in early or leaving late is usually a good way to be seen as a hard-working individual but it is also a good way to burn yourself out. Try to pick one or the other if you can, and either be the guy that stays late or the guy that is always the first in the office. Earlier in my career, it was always easier to stay late and be the night owl. As I got older, it fit my schedule better to be one of the first ones into the office. If I had to pick between the two, coming in earlier seems to be the better option when it comes to what looks better to a client. It also allows for plenty of time to relax and decompress in the evening before the next day begins.
Try to do a frequent health check on the image you are putting forward, whether it be your attire, your work ethic or how much time you spend chatting with others in the break room. The perception that client has of you will be a major factor in your ongoing work.
Are you interested in starting a career in consulting? Be sure do read the full book Jack of all Trades Master of Some; An Introduction to Consulting available on Amazon.