Store your cardstock in colours. I store my A4 cardstock in hanging files in a filing cabinet and my scrapbooking sized cardstock in the boxes that you can buy for storing lever arch files in. My paper is filed on it's edge for easier access because if you stack them up it is always the sheet at the bottom of the pile that you will need. If you have it organised by colour it is easy to grab the file or pile of card to select the exact shade that you need for your project.
Have a great Saturday! Thanks for stopping by.