What helps greatly in this is the juicer you are using. A masticating juicer will get more yield than a centrifugal juicer especially when it comes to leafy greens - which is what you want in your daily juices - kale, chard, spinach. You can also look them up on WolframAlpha individually to get a good look at what each is estimated to contain. You can use fillers such as celery and cucumber. But most folks base their juices from carrots, apples. I enjoy using peppers (sweet peppers, bell peppers) as they produce a nice yield, second are beets. Try and stick with more greens and less fruits.

Unfortunately the juicer that I bought (Breville BJE510XL), is in fact a centrifugal juicer, not a masticating juicer. After doing some research, I realize that this was a poor decision and will return this one and go for a masticating one. Right now I am looking at the Omega J8005, which is #3 on the TopJuicerMachine.com page recommended in this subreddits sidebar. I am also looking at the juicer that you are currently using Omega VRT330. Besides one being vertical and the other horizontal, I can't seem to find the pros and cons of each one. Reviews wise, the J8005 wins with a 4.5 Star Average (239 reviews) while the VRT330 has 4 Star Average (76 reviews). Price wise, the J8005 also wins @ $252.43 while the VRT330 is $314.99. What are your thoughts on the benefits of each and why the VRT330 is more expensive than the J8005?