The following is an example of creating a 'diamond knurl' (commonly used to improve grip on everyday objects). You may set dimensions of your preference while using the below steps as a guide to essential geometry operations:
1. Create a cylinder of length 30mm and diameter 20mm. In this case, the top & bottom edges have been rounded to 2mm each.
2. Place a sketch grid at the intersection of the round and cylindrical portion (above right hand figure)
3. Draw two construction lines, centered at the cylinder's origin and with a 5 degree separation.
4. Sketch the following profile where each line is 0.617mm and perpendicular to each other.
5. Switch to 3D mode. Select the surface you have just created and click Pull -> revolve. Choose the axis of the cylinder to revolve around and then enable 'Revolve Helix - right handed' in the options tab on the left.
Set a height of 26mm and Pitch of 120mm.
6. Select the four faces of the ridge and choose the move tool.
7. Drag the move handle to the cylinder's axis. Now choose 'create pattern' in the move tool options.
8. Rotate the move handle along the z-axis (blue curved arrow) to generate a pattern of 30 ridges (count = 30)
9. Select one of the profiles sketched earlier to create the ridge and then do PULL -> Revolve (along cylinder axis) -> create helix (left handed). Pitch at 120mm and height of 26mm.
Before completing the helix operation, click on ADD under PULL options.
10. Similarly to step 8, create a 30-count pattern of left handed ridges which intersect the right handed ones.
11. Select the combine tool; choose the cylinder as the target object (green colored) and the 30 left-handed ridges as cutters (in yellow).
12. After the combine operation is complete, we need perform a 2 stage removal of the artifacts. Firstly, the cutter objects (30 left handed ridges pattern) can be deleted.
Next, the cut-out portions from the right handed ridges need to be removed to get the diamond shapes.
On the left hand tab, you can find the advanced selection pane. Group select them and delete.
12. (2nd option) Alternatively, you can triple-click select a member of the left handed ridge pattern and then go into the selection tree to group select all right-handed ridge cut-outs. This will bring together both selection batches and you can choose to simply hide these solids from the structure tree if not deleting them. Watch this animation:
Tip: You can increase the number of ridges (pattern count) to create a more detailed knurl.
Example 2: Knurled thumb nuts for better grip
Watch this screen recording for how to knurl the outer surface (right-click and save as to download it):