First, on the very back of this machine , there is a pair of brackets and a curved slide . It may have a thumb screw, or a small maybe a 8mm nut. this sets the height of the step of the toe foot , the back foot responds to the toe foot . At the lowest setting the machine is working very lightly. at this point both feet are rising/ lifting about the same height. This setting is for flat work . And I believe the best setting for adjusting tensions both top and bottom. Set your stitch length at about half way just not full way, and try this on blue jean fabric. Also back the top tension off 1/2 turn to start , and use black on top and white on bottom ,for good contrast......we may need to adjust the check spring and the bobbincase opener as well .....does this machine have large bobbins.. good luck Dave1.