You may not have thought of this before but your body is a measuring device you always have with you.
For example if you're of average hight- 1.) Trim hedges to chest-hight-you may have to adjust a bit if the ground slopes downward 2.) Prune roses to chest-hight- most of the year in November-to waist hight in Jan-Feb - to knee hight 3.) Plant summer annuals a hand-span apart, tip of thumb to tip of - middle finger (8in.) Use same distance for groundcover plants including strawberries 4.) Plant small shrubs, like Azalias, your forearm+hand length (about16-18in.) apart 5.) Optimal planting bed width is 2 hand+forearm lengths(18 + 18 = 36in.) That way you can reach the center from either side. 6.) Planting seeds you use your fingers to determine depth. The distance between joints in your fingers are approx 1" (seed depth depends on the size of the seeds and will be marked on the back of the package) and the distance between seeds is 3" (if you are doing the French Intensive Method, which just means you can plant seeds closer if you amend the soil with various nutrients, compost etc.)