“How much should I be writing?”
The answer is, “As much as you want.” Your goals are exactly that, yours. Writing is one of the few endeavors where you get to be totally selfish (unless someone else is paying you for your time.)
But true productivity isn’t just measured in number of words or pages. Don’t get hung up on that. Sometimes you can spend a lot of time and not get many words on the page. Other times you write a lot, and the next day, you throw it away.
An anecdote ascribed to Irish author Oscar Wilde is right on point. Asked, “Well, Mr. Wilde, and pray how have you been passing your morning?” he answered, “Oh! I have been immensely busy. “I have spent my whole time over the proof sheets of my book of poems.” The man inquired about what he’d accomplished. “Well, it was very important,” said Oscar. “I took out a comma.” “Indeed, is that all you did?” “By no means; on mature reflection I put back the comma.”
Wilde was pulling his interrogator’s leg, but he still speaks to what we’re discussing. What’s important is that you set some kind of goal—as Wilde did. He chose time and felt that he’d put in a good day’s work. You can choose how many days you’ll work, the number of words or pages per day or per week you’ll complete, or perhaps, the number of hours you’ll sit in front of your computer or with pencil and pad in hand. After that, your goal is to be consistent.
If you are consistent, you’ll be amazed at how rapidly you complete worthwhile writing.