I created these labels from the Cowboy CB3200 manual, tips I have learned over time on setting thread tension, and some needle/thread/thickness recommendations from WizCrafts over at leatherworker.net, printed them on a clear inkjet label sheet, and affixed them to my machine.
Now all of the information needed to match the needle and thread to the material thickness, to determine which direction in which to insert and thread the needle and bobbin, and to adjust the tension is right on the sewing machine.
Following are a couple of pictures of the labels on the machine and here is a pdf file of the labels that you can download and use to print your own.
Hope this helps.
Michael