Some are redundant. I will probably think of more.

• Use the 'Working Dims Plan' Layer combination.
• Option+click on existing strings to maintain witness line justification as you move in.
• To add one string's ticks to another, select the string to keep and Cmd+click on the string with the points to add.
• Use the arbitrary angle setting when dimensioning walls, for auto-orientation.
• Use the 'place, rotate, drop' construction method with the CL object.
• To graphically justify a group of witness lines: Select the ticks. With the dimension tool, click on the segment and drag it to the desired justification point. Useful for backing up a few witness lines where the plan is very near.
• When you select a tick, the element the tick is connected to will briefly show as selected. To maintain this effect long enough to actually observe it, hold the mouse button down on the tick.
• Ticks can accumulate at a single point. If you try to delete a tick and i stays put, keep trying.

See also:
Dimensioning, General Principles

When dimensioning, strive for stunning, perfect, complete, beautiful clarity. I'm serious.

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