When I realized I wanted to finally take a dive in the watercolor pool, I really didn't know where to start. Choosing the paper seemed as good a place as any. I took a class at a fabric and craft store and we were given cold press paper as a part of our little supply kit. Cold press is great for getting that bumpy texture that can accentuate watercolor washes. The downside of this is when you go to scan and you can't get a good scan or print because of that texture, it gets in the way for me.
I was then introduced to hot press paper when I took a landscape painting class and this was intimidating. The paper has no texture, super smooth but you can get frustrated because you don't have as much time to play in the washes. When you are first learning water to paint ratios, hot press paper can be tricky. But it is wonderful to scan and print when you work with hot press. No bumps, no lumps, no coconuts. ;)
Soon after that I think Tracy Bishop, an awesome watercolor and digital artist, told me about soft press paper. Now this paper is like hot press and cold press had a baby. There is some texture but just enough, super light. This can still be a problem with scanning but you get the play time like cold press and a little less intimidation than hot press.
Papers come as free sheets, in block form and in journal form. I tend to lean toward the blocks for my premium paper. Pretty much when I want to get a print from my painting. But when I am on the go and I want to experiment, etc, I use watercolor journals. My favorite so far is my Moleskine watercolor paper journal because I like the way the paper takes the paint. I'm able to mix just enough to simulate washes like I get in my premium paper.
Lastly there is mixed media paper and this is what I like the least. I bought a Strathmore Mixed Media journal and the texture is super smooth. However, it resists my paint from time to time and that can be annoying. It is a good journal just for messing around without investing a lot of money. There are 64 pages and you don't get much transfer from the front of the paper to the back.
If you are starting out I would go the same route I did with cold press paper. Then you can see how you like the texture and many of the cheaper brands/student grade are in cold press by default so you're golden.
You can see a list of my favorite watercolor resources and more right here.
P.S. If you are a busy illustrator who needs help with success in your practice and goals, this printable worksheet helps you prioritize your day. You can organize your day, list your goals, make notes, track your habits and sketch daily. An awesome recipe for success, baby steps count. Get yours here!