As a creative person, you know. You know when it is good and you know when it's not so good. As Mr. Drake says when I ask him...Is this wax seal okay (show him some mess)? "If you have to ask, you already know the answer." So wise, that man.
Here's how the process works for me with my custom work, starting with the creative consultation, dreaming up ideas together. You come in and have a spark of an idea, like your love of the sparkly sea water, or the cave from a vacation in Mexico, or the view from your childhood backyard, or the font from your parent's wedding invitation (all these are real inspirations to our invites). I messily sketch out in our consults, and honestly, I may or may not know at the time that it will turn out like we both envision.
One of the things I have learned in 11 years of doing this, is if the work is good or not. If I'm painting and it's just not flowing, I stop and come back another day.
Like this day: everything was in place, weather was gloomy, (who wants to paint when the weather is nice?!), music on, etc. But nothing looked good. I painted some stripes so the day wasn't a total waste and put the paints away.
Then a few days later, it was raining and cold, and I just wanted to work from home. So, I streamed Season 5 of Girls and painted for 5 hours straight and created some work that I liked. All these flowers that turned in to a pretty frame for a client's invite:
Plus I finally painted some poppies that I love:
There's a small smile when I'm working and it's going well and I like it. I literally physically smile at the results. So, for me, that's when I know.
When do you know if your work is good? Do you trust your inner knowledge, or do you look outside yourself for the answer?