I'm using the Seafoam kit, which was designed by one of my favorite crafters, Elise Blaha Cripe. When you purchase a Project Life kit you get tons of cards - some 4" x 6" cards and lots of 3" x 4" cards. Most people do a two page spread for each week and they will likely use all of these cards.
For someone like me doing one two page spread per month this is way more cards then I need. Because of that, I'm pretty free with my use of the cards, cutting them apart, punching shapes out of the cards, etc. It's kind of nice to have that freedom and I can even see myself using the cards for other projects.
The 4" x6" cards all have a white space for a title which is nice, but honestly I wish the kit had some cards without the white space. I have found myself covering it up with photos or embellishments, and I've even cut the colored portion of one card to hide the white space on another card. Not a big deal, but one thing I've found slightly frustrating.
Because I've been cutting the cards apart I've ended up with bits and pieces which I've saved in a clear envelope to use later. I've also saved other shapes that I've cut out of cardstock so when I need a little something to add to my project I have a nice collection of "stuff" to choose from.
When I'm not working on Project Life I keep all of the cards stored in the nice, white box that the kit came in. I store the clear envelope of "stuff" right on top so it's all together, and then the box goes into my craft armoire until the next time I'm ready to work on it.
I'm really glad that I decided to do monthly spreads rather than weekly spreads because I know for sure I'd be behind by now. I have a lot of craft projects I like to work on and if I were doing weekly spreads I wouldn't have much time for anything else. I don't print photos at home (which I think would be necessary in order to keep up every week) so doing monthly spreads means that once each month I go through my photos, order what I need and get my spread done in just an hour or two.
If you want to read all of my Project Life posts just go to the archives page and look for 2013 Project Life.