I use a 3-gallon plastic bucket because I found it at a thrift store but you can use a 5-gallon bucket or even a large trash can filled only about a third full.
To create the oiled sand I used general all-purpose sand and the most inexpensive motor oil I could find at the local big box store. You can use mineral oil or vegetable oil but for me the motor oil was less expensive. The success of the project is not dependent on the quality of the oil. A 5-gallon bucket requires approximately ½ gallon of oil so for my 3-gallon bucket I used a total of about 1 and 1/3 quarts. That is enough oil to moisten the sand but not enough to create a drippy mess.
First I filled the bucket about half way full with sand then poured half the oil over the sand’s surface. I then stirred the sand to mix in the oil. Finally I added enough sand to bring the level to within 3 to 5 inches of the top of the bucket, poured in the remaining oil and mixed. And there it was, oiled-sand, that not only helps clean my tools, but coats them and protects them from the elements.
To actually clean my tools I submerge my single bladed metal tool such as a cultivator, trowel, shovel or weeder, into the sand and work it up and down and all around to clean off any soil or sap or other plant substances and to coat the blade with the oil. Note, I never clean any scissor type tools such as clippers, shears etc. in this manor because the sand will damage this type of tool.
If my tools are excessively dirty, such as coated with clay like soil, I wet and scrub them with a brass brush before treating them to their sand and oil bath. Rusted tools are pre-cleaned with steel wool to remove the rust and then submerged in the oiled-sand.
My oiled-sand has lasted for about 8 years and some day I may have to add more oil but so far so good. This has been an inexpensive and easy way to care for my expensive garden tools.
Hope this hint has been helpful and I look forward to seeing you in the garden.