Structure-Function.org

Ulna, Right

1. Radial notch
1. Proximal radioulnar joint with radius
2. Olecranon process
3. Trochlear (semilunar) notch
2. Humeroradial (elbow) joint with humerus
4. Coronoid process
5. Ulnar tuberosity
6. Interosseous border
7. Head of ulna
3. Distal radioulnar joint with radius

On the proximal end (A to E) of this long bone, note the "hook-like" appearence of this structure, as well as the raised surface (E) that tells you this in the anterior view of this bone.

Then, if you remember the shallow depression (A) faces laterally, you should be able to work out if this bone is from the left or right side.