Advice: You don't know EVERYTHING about your characters

I've seen a lot of people writing stuff, excruciatingly painfully explaining every single twitch that character had in the first few pages of that story. People, we do not need to know the entire biography of someone right when you open the story. Why? Well, first of all, because we do not care. We are not yet attached to that character emotionally, so it's definitely not interesting. There are few authors that can pull this off, and they have their methods.
Best was to describe characters is, first of all, gradually, over the entire length of the story, so the reader gets to know it and gets attached to it, and then, use a lot of dialogue and interaction. You can very well describe your character through dialogue, he can answer inspired questions put by other characters, so you don't need to foolishly explain everything to your readers.
That should be a ground rule. Your readers are not stupid. If you hint them something, they will probably understand what you meant without trying to give them every single bit of information you have stacked up. Also, don't have every single character of your fully developed in your mind in the beginning. Of course, if that happens, it doesn't mean it's wrong, but you will be amazed at how much your character can evolve while you're writing your story. Every twist and turn in the plot, will obviously affect your characters, and through that you will find out how they're shaped and how they react to different impediments. Test yourself, put a character through a few different actions that would obviously endanger it. Write down how he or she would react to that. After doing that, you'll have a much clearer picture on how brave your character is. You can do this for a bunch of other qualities you can think of.
I hope my advice will help you, and hoping to see some feedback here.
Start writing.

Advice: Don't put too much of yourself into your writing

If there is one thing I learned while writing short stories and starting to write a novel is that putting too much of yourself into something you write doesn't always work and doesn't always appeal to your readers.
Yes, it's fine to distinguish one of your characters with your qualities, flaws and maybe something really exciting that has happened to you and you want to share with the world, but writing too much about yourself into a fiction piece will not work.
Why? Because, let's face it, you as an individual, unless you've been to war or experienced a truly traumatic event, will not have a story as interesting as a "fictional" character you can mold and turn into anything you like.
If you want to tell your life story, wait till you are famous and then publish it as non-fiction. Till then, let your characters be free, don't assimilate them with you.

Advice for newbies

How hard is it to be published when you never wrote something before? That's a question I have been asked quite frequently in the past few weeks. The truth is, I usually tell them, that I have no clue.
There's something to do with imagination and intelligence, but there is a great deal related to sheer luck. Sometimes it's just NOT gonna be published. What my advice is for anyone trying to find its way into the publishing spectrum is "try as much as you can". Stephen King submitted two novels to publishers until "Carrie" was finally accepted. Rejection doesn't necessarily mean that you are not good, it might just mean that you are not writing what the publishers have to send to the market.
So, check the bestseller lists and see if any of the genres of literature there are appealing to you. If so, you're on the right path.