The Easy1541 cable
You need the following parts to build this cable:
Step 1. Solder one end of the cable onto the DIN plug.
Step 2. Solder the other end of the cable onto the parallel plug. You should have the following connections:
Note that pins 4 (CLK) and 5 (DATA) of the DIN plug are connected to two pins each at the Amiga end. You can do that with a pair of short wires cut off of the cable.
You can find the description of all parts used on the diagrams at the legend page.
Source: The Joe Forster-STA homepage