designingbilly - Knowing when it's just right enough to send out to the public/client?
thadcoxdesign - I think this is instinctive and comes with experience, but I find it comes down to 2 things.
Firstly, have you answered the brief? This is either a yes, or a not yet. From the outset it must be made 100% clear what is required. Go back to the initial agreement and check that you have fulfilled what you are being paid for.
If you have delivered on this, then it's over to the second part.
You have to be honest with yourself and ask yourself "Could I do more?" If you can, then it isn't ready. You have to reach a stage where you have answered the brief, met the requirements and have refined the solution to it's best possible outcome.
Anything that falls short means it's not ready.
Imagine you are having your portfolio reviewed. It's just you, your portfolio and your prospective employer or headhunter. As they go through each piece of work, what are you feeling deep down? As they approach any piece of work, do you anxious, nervous, embarrassed or excited? How will it hold up against all your other work?
If there is any negative emotion attached with someone seeing the work, it's not ready. If you are excited to show them, it's probably ready.