I'd suggest obtaining a small dry erase whiteboard. I've seen these offered in office supply stores as small as A4. Use a permanent marker and ruler to mark your guidelines on the board, and allow time for the marker lines to cure, then do your writing practice with dry erase markers. Write, erase, repeat.
Now, that said, I'm not certain dry erase markers are much more environmentally friendly than recyclable paper -- but the volume and mass of waste should be significantly reduced and if recycling isn't available, this would surely be an improvement over landfill disposal of all that paper. Once the up-front cost of the board and markers is sunk, it will also save money over the term of a few months.
Some brands of dry erase marker may take off the "permanent" marker dyes -- which generally stay on the surface, and are permanent only by virtue of needing a more aggressive solvent than is usually used for cleaning. From comments, pencil lines on the dry erase surface may stand up to gentle dry erasing better. Another option is to do tests to find a marking method that chemically bonds to the dry erase coating.
Still another potential solution is to have a couple sheets of your practice paper laminated. In this case, the markings that need to be permanent are under the plastic layer, and you'd use either dry erase or wet erase markers for your practice (wet erase will certainly work, dry erase would require testing, but should come off the laminating sheet).