When using a stick welder it is often not easy to begin an arc exactly where you want it. Some risk damage to their eyes by peeking out from under the hood. But, a carbon rod allows starting a bead exactly where you want it to begin.
The piece of steel in the photo is about 3 inches across. I ground the paint away so an arc can start easily. The arrows were made with a felt tip pen. This Instructable will show how to start an arc in the center area between the four arrows.
The portion with paint removed at the lower right corner of the photo is only a place to attach the welder's ground clamp.
Step 1: Prepare and positon a carbon rod
Welding supply houses usually sell carbon rods. These come with a heavy copper foil on them. Touch the foil to a grinding wheel from the tip back a couple of inches. Peel the foil away from the rod.
Touch the tip of the carbon rod to the steel just behind the point where the bead is to begin. Be sure to wear welder's gloves.