Instead of cross hatching, I often hand quilt my applique quilts with the Baltimore Grid pattern. The Baltimore Grid forms an X in the center, and lines echo from that X. It is easy to do!
The Baltimore Grid is easy to mark to fit any applique design. You can alternate direction on each block, or follow the X pattern across an entire quilt. Here is how I used the Baltimore Grid pattern on my Bluebird Basket quilt.
From the back:
How to Mark the Baltimore Grid
For a single block -- say you have a 12 inch block -- put a pin at each 1-inch on all 4 sides of the block. These marks will be evenly spaced across the block. A block seamline or sashing can be the stopping point or change of direction. Mark diagonal lines with a hera marker from point to point, or use blue painter's tape to mark the quilting lines. If you use a water soluble marker, you can mark dots at the inch marks to guide placement for each line of painter's tape. Be sure to quilt along the correct side of the tape.
For blocks that do not measure in exact full inches, cut a length of paper the same length of the block. Fold the paper into even sections (in half, then half again, etc.) until you have folds that are all equal, close to an inch or so. Mark the correct fold lines on the paper with a pencil. Use the marks at the edge of the paper to place pins or marks.
On my large center block, I used the red dogtooth as equal points, and at the center sides, center top and center bottom, I changed direction. Marking only a quarter of the block at a time, I used a long strip of blue painter's tape at vertical and horizontal to mark my center stopping points. I marked the lines with a hera marker along a clear plastic ruler. You don't see a center X because of the applique, but the diagonal lines sometimes continue through spaces between the applique.
There is also a feather vine here, which interrupts the grid, but the Baltimore Grid lines are all continuous, out from the center on this quilt and through the borders.
Here's another bonus - when you finish quilting the grid, maybe you will want to quilt some more, and decide to do cross hatching, or add quilting in some or all of the quilt. You are halfway there! That is exactly what happened with this little quilt. When I pulled out all the basting stitches, it just was not enough quilting to suit me. The quilt was nice and square, so I bound it, and then quilted between each line, all by eye - no more marks were needed.