Your cream will go through different stages.
First it turns into heavy whipping cream.
Then it begins to look like feta cheese.
You know it is complete when the buttermilk has separated from the butter. You will have chunks of butter in the liquid.
All you do is scoop out the butter with your (clean) hands, take it over to the sink or over a mixing bowl and squeeze it to get the remaining buttermilk out of it. And there you have it...your butter!
What's left is buttermilk. So place it in the fridge or measure it out into ice cube trays for future recipes.
Raw butter can be stored in your freezer for up to 1 year or refrigerator for 6 weeks. Grass-fed raw butter is considered a good fat and tastes good. :)
(Where I live it is not illegal to buy raw milk or cream. Our raw milk comes from a clean dairy that gets inspected and has to have a special certification to sell raw milk.)