What I have done, without a walking foot, is to do a diamond pattern. I chalk mark two lines, corner to corner, crossing in the center. After safety pinning within the four quadrants created by my lines, I begin in the center and stitch out along one of the diagonals up to a corner. Then I use a guide bar to set the next row, and continue that way filling in that quadrant with diagonal lines spaced as appropriate for the pattern. I repeat with each of the quadrants, always working from middle out. That way I have avoided bunching since everything gets smoothed out from the middle out.