1.Dig up potatoes .
2.Dig hole.( an optomistic hole and observe soil strata in the process )
3.Place in straw
5.Cover with straw and grass clippings.
6. Cover with soil and firm with shovel/ spade
7. Dig up again as required or if you forgot to keep some back for use!
If you have a light soil of course just cut the stalks down and leave in-situ untill needed. Works well on wet soils. There are other versions of this which are above ground only. This method is how one of the students at Park House used to do it growing up.Great debate was has as there are any number of ways to do this.