It looks like a later model of my 1036. This model was built from 1982 - 1985 and has plastic gears. It has a wind in place bobbin (Touch & Sew type). If you push down on the bed in back of the needle plate, it turns into a free arm. Push down on the stitch length dial to sew in reverse.
http://www.sewusa.com/Threading_Diag...ng_diagram.htm
This link is for a 1036 but it will help you with threading, and winding & changing the bobbin. Singer has manuals available to download for $10.
(I found one on ebay and the pictures aren't clear enough for me to be 100% certain. What I say after this is based on what looks like the same parts as my 1036. If any of the following does not make sense, disregard it.) If the stitch selector panel shows the different stitches in different colors-red, white and yellow, adjust the stitch length dial to the same color as the stitch chosen. The white stitches have a bit more leeway for stitch length.
The stitch selector dial is very different from the 1036. On the 1036 you need to push down on a lever before you can turn the dial.
The 1036 needs a buttonhole foot to make buttonholes and has only one buttonhole setting on the stitch selector panel. I see that the 1425 has a lever with a buttonhole picture next to the presser bar just like the 1036. On the 1036 you need to pull it down and forward to make buttonholes. The buttonhole foot hits the lever when it's reached the end of the buttonhole length on the left side of the buttonhole. It takes a few zigzag stitches in place and then makes the right side of the buttonhole.
Hope this is a help to you.