Now this will be the hardest part of the process. Just shake the jar vigorously for up to 15 to 25 minutes. You will feel the cream thickening during the later part of the shaking process. Just keep shaking till it gets to the desired creaminess / thickness you prefer. Once you have it then all you do is add the salt (optional of course). At this point just mix it and if you want you can place the butter in a bowl or other container of your liking but you can also just leave it in the jar. You might also consider adding in any flavoring or spices to make a flavored butter. I made some ranch flavored butter for mashed potatoes for dinner. It was delightful.