The two things that trip people up are:
The second is purposefully a bit vague, but just visiting the home page doesn't count. You need to read a question or some other action that demonstrates you are using the site in some capacity.
The first is mostly a problem if you aren't on a regular schedule. Weekends are especially tricky for me in California since I might log out on Friday afternoon before the end of the UTC day and not come back until Saturday evening. Even though I've been to the site on two consecutive localtime days, I've missed a UTC day.