Staying aware of how wet the brush is compared to the paper will keep you out of all kinds of wetness trouble. What is traditionally called "wet-into-wet" painting should really be called "wet -into-wetter"'
I find it much easier to tell how wet the brush is than the paper. I can always try out the flow of the brush on the palette, or on a piece of practice paper, whereas, until I commit to a stroke on the actual painting, I can't be sure how wet that piece of paper is.
It will take a little while before you have a good sense of how long the paper will stay wet in any given set of conditions, so, for now, I recommend making it too wet. you can adjust how thick the paint is on your brush to compensate for the wetness of the paper, and still get roughly the kind of edge you're after. The density of the paint on the brush is another range of possibilities you will come to know better and better with time. Since so many painters make much paler paintings than they intend, here, too, let's err on the side of too much pigment.
To practice this balancing act, look over the photo you brought home, or find one of your own, and identify a passage that will require wet paper to achieve the edge qualities you see.