Line is expensive and the most fragile connection to the fish, so I like to use a top-shot system on all line classes that I fish. For 80- and 130-pound line, I fill the reel with Dacron backing and splice in a mono top shot, changing out the mono as necessary and leaving the Dacron in place.
On 50-pound class and down, I fill the entire spool with straight mono, usually a high-visibility color, to start. After using the line some and cutting it back around 100 to 200 yards, we strip off another 100 to 200 yards of line and cut it off, leaving the spool two-thirds to three-quarters full, depending on the size of the reel. I then tie one 2- to 3-foot Bimini twist on the line from the rod and one on the spool of new line.
Pass the loop from the rod through the loop on the spool and all the way around the spool, forming a loop-to-loop connection, then pass the rod loop around the spool again to double it up. Put a little spit on the loop connection, and carefully pull it tight while holding the Bimini knots, making sure both loops are even and centered.
To mark the connection, use a black marker pen and color one of the Biminis black. As you start to fill the reel, place the black Bimini around the center of the spool, and watch it disappear as the spool fills up. Now as you use the line and cut it back, you will start to see the black indicator around the spool’s center, and you will know how close you are getting to your top-shot connection.
— Capt. Randy Baker