It takes many steps to draw a comic book page. After the starting stages of getting ideas and writing them down, the artist must do layouts, sketch the characters and backgrounds, tighten the drawings and finally do the lettering. The materials and tools that Barks used for his artwork is described below.

Barks used Strathmore 500 Series Mediumweight Bristol.
It is 100% cotton fiber and acid free and takes repeated erasures and reworking without feathering.
Barks divided the sheets into two sections and finished one part at a time.

My best work has always been on Strathmore medium surface. In the old days I was furnished with Strathmore, and my style was more detailed and the characters more expressive. Then along in the middle fifties the office got on a money-saving kick and began furnishing us artists with a clay-coated import from Germany. The pencil and pen dug into the surface and couldn't be guided with any finesse. The result was a tightening of the lines, less bounce to the characters.

    After the story was written Barks would sketch out the panels using a pencil with a light blue lead. Blue colour pencil is not picked up by the cameras in the final production stage. This enables the artist to draw rough lines without having to erase afterwards.

Barks then used pencils, Dixon Ticonderoga No.1 Extra Soft, and No.2 Soft, to trace tighter lines on top of the loose blue lines.

..........
The next stage was a very firm line drawing using a Scripto mechanical pen with standard diameter (.046 inch) long leads. The sort of package shown was actually used by Barks but has long since been discontinued by Scripto.

Barks always used Faber-Castell's Higgins Black Magic Waterproof Black Ink in 29ml bottles. The ink goes on smooth and does not leave a greyish shine. It is very black, and dries quickly which is important because ink that sits for a long time without drying, can be accidentally smudged.

.... ........
Different pens with a variety of metal nibs that are attached to wooden holders. Each nib was used for a specific purpose. For instance the Speedball B (at the far left) was used for lettering.

One of Barks' favourites was the American Esterbrook 356 pen with extra flexible action.

...
Barks used a variety of brushes for special lines and solid black areas. He preferred the Red Sable Watercolor brush series from Winsor & Newton. Despite the name (sable) the brushes are manufactured from selected marten tails which gives them a very fine point which will broaden and thin quickly in use. This achieves a thick, varying line that can be easily controlled by the artist.
Two examples are shown here - the flat No.2 and the round No.7.