"Rewritable" (practice) Paper
One of the newer trends in brush calligraphy, is using rewritable practice paper. I've recently purchased some examples of these (in various sizes) and (so far) they're kind of "fun" to practice with. They certainly are more convenient to use for practice, they have a lower potential for making "messes" and they don't "use up" valuable materials ("paper, ink").
In the past, I've had students use the small (and inexpensive) "chalk-boards" for temporary/repetitive brush practice. The major drawback to "that" method, was the reflection of "Paper/Ink" interaction (they were different between the two, which could lead to a false sense of ability with the "chalk-board" method).
The paper is utilized by "wetting" the brush (similar to "inking", but it's an acquired knowledge, much like learning how much ink to use. The differences in consistency between the two mediums is easily learned though, and shouldn't be a concern), Then using just as with ink upon the paper.
The paper doesn't tend to "bleed" too badly at all (which I admit was my initial concern). Drying/recovery time will be dependent upon the level of Humidity present where your at. I live in the Midwest (Kansas city, Missouri), it's the middle of winter (15 degrees outside) and we don't own a humidifier. Drying time is (on average) about 10 to 15 minutes.
Considering the savings in material (alone), I feel this is an acceptable "inconvenience". If your looking to practice the basic "strokes" (or even complete "kanji") I think this medium is definitly worth the (minor) investment.
The "average" cost (via "E-bay") is (presently) around $10 for 10 of the smaller "sheets" (approx. 10" X 15") or a single Large sheet for $20 (approx.17" X 28"). The prices vary (I've seen them as high as $75 for the large one), but "shop" around, there are numerous people selling them.
There are also sheets for practicing the various "strokes" (I have one of those as well), but (IMO) they aren't very good "examples" and would instill bad practice habits through their use. "I" don't recommend them.
You won't be able to use your "regular" brush(es) on the paper though, as residual "ink" (in your brush) will permanently mark the practice paper. They are intended to only have WATER utilized on them. They (often) come with a brush that can be used (and obviously hasn't been used with "ink"). Though not of the best quality, they will serve the purpose. If you don't care to use the supplied brush, you can use your own (NEW) brush, just remember to not use it for your "inked" projects, LOL (unless you don't plan to use it upon the "rewritable" paper anymore).
I also acquired one of the "scroll" practice sheets, again, I don't care for the examples, but they do offer the ability to practice a consistent "size" and placement for a (horizontal)"scroll". The characters are approx. 1-1/2" and there are about 8 kanji/column and approx. 20 columns. The entire sheet is approx. 18" X 48". Though "they" recommend the use of a "small" brush, I had no difficultly brushing them with the larger (2-1/2") brush. (I can guarantee you that you won't be able to brush the complete sheet, before the first one's are dry, LOL).
Over all, though the "feel" is not exactly like that of using "ink" on paper, for practice/learning purposes, I think these are something that should be investigated, and determined if they would serve your practice purposes. The "cost" is cheap enough, that you shouldn't get hurt (too badly, LOL) even if they aren't for you.