1. Go to a farm
You have to find some real goats. Fur and everything.
Do not wear your favorite purse. It will be chewed.
Be prepared to socialize. Kids can be very playful, but unless you are a rockstar or a politician, crowds can be intimidating. (100 baby goats at the farm in the pictures!)
2. Draw realistically
Remember when you believed you are going to be a graphic designer and you didn't predict any goat encounters in your future? Forget that nonsense. Every artists needs to draw a goat in their lifetime. That's how you build a success story.
3. Develop a whimsical character
Now that you have become a goat connoisseur, it is time to develop a character for a potential story.
Quite the most difficult part of the process. Unless you have already spent hours in the cold (+rain) drawing realistically. Or you got attacked by a bear while drawing. Or you saw Anthony Browne and had no idea he is famous.
Right… drawing whimsically. Frankly, I have no idea how you do that. I am trying to make sense of it myself, with each drawing. So you'll have to figure it out yourself. It's just you and the goat now.