Who ever is running the sample for you should give you the tool to do it with. Least they do here. Round tube the size of, say a half dollar. Bout 2 foot long? Turn it into the ground till the handle is 6 inches or so from the ground. Put the sample in a bag.
Be sure to take samples from several areas to be sure to get an accurate report.
For row crops the depth is 6 inches, for pasture 3 inches.When I did a soil test they did not give me a tool.Would have been nice if they had..... ;-) :cboy: