I only picked what I know I will use. When foraging leave some for others, it's the polite thing to do.
All I do is peel and core them, slice them and put them in a large sauce pot with a little water. Just enough to keep the bottom of the pot from drying out until the apples start to break down.
Add a little lemon juice to prevent browning (about a Tbsp).
Add sugar to taste.
I add about a half a cup to help with the cooking process. A little sugar pulls the juices out of the apples. I then wait until the apples are cooked down to add more sugar and taste it to get it to the sweetness that I like.
You can use a hand mixer to make it smooth or leave it chunky. I like mine chunky.
Then can them in a water bath canner for 20 minute for pint jars.
You can get instructions here