Is 4GB of cellular data enough for one iPhone 5S user?

I don't have Wi-Fi at home however when I'm at work I have access to free, fast Wi-Fi and I work Monday through Friday. I'm mostly going to use those 4GB of cellular data only on Saturdays and Sundays as I'm obviously not at work. I'm a heavy data user, I use YouTube, Facebook, surf the web, Snapchat, Hulu, & Netflix. I was planning to go from 4GB to 8GB instead as it will accommodate me better. I will be paying $140 monthly for everything tax already included. It's been 3 days and I have already killed 1.1GB since I'm on my Christmas/New Years vacation but at the same time I've been trying not to use up a lot of data. Would you guys say 8GB would be good for me for only Saturdays and Sundays for one month?

Yep!

8GB is better.

The main thing that eats through data is video, and video on an iPhone uses up a couple of megabytes per minute. Four gigabytes is 4000 megabytes, so it corresponds to about 12-24 hours of continuous video. If that's more than you watch in a month, than 4 GB per month should do.

Depends on your personal circumstances and usage