The first Tip I would love to offer…. Purchase a good paper trimmer! Most paper come’s in 8 1/2″ x 11″ or 12″x 12″ packs. Even if you plan to use the full pages to scrapbook or use them for other projects, it is always good to have a good trimmer. You can also use this to trim pictures, window sheets, newspaper articles, etc. It comes with a scoring blade, also. This is what I use daily to score my cardstock when creating a greeting card. I always score my colored cardstock to get a nice, crisp, even fold!
Check out our Stampin’ Trimmer: 
Item #126889
This is the paper trimmer that all other paper trimmers want to be! This lightweight, portable trimmer is specially designed to make stable and straight cuts.
* Full 12″ cut or score
* 1 cutting and 1 scoring blade included; replacements and specialty blades available
* Extra-wide, 6-1/4″ cutting base for most projects; 14-1/2″ extendable ruler for large projects
* Ruler and grid protected by durable plastic cover
* Point on cutting handle for precise measuring
* Right-side grid for cutting thin strips
* Includes storage compartments for extra blades, Bone Folders, and more
* Replacement mats available
Of course there are other paper trimmers, but this one is awesome!!! If you want to cut more than one sheet at a time, you may want to consider investing in a good table top paper cutter with a side arm. That is what I have in my office, and Love it!!!