Ok, this situation recently came up with one of my friends. She had been asked out by 3 different guys in less than a week. If 3 people had asked you out, how would you go about choosing who you would go out with, what would you say, that kind of stuff?
First come, first serve!
Why can’t she go out with all three of them? It’s called “dating.”
Why go out with any of them? They could be ugly, have mental case personalities etc.
If I didn’t want to date any or all of them, Id simply say to each one ‘Im not free to date now.’
Monogamy is over-rated. 
There’s nothing wrong with dating all three, as long as she makes it clear that she isn’t in an exclusive relationship with any of them.
I’d date all three, unless they all asked for the same day, in which case I would say yes to my favorite and expalin to the others I had a previous engagement and take a raincheck.
My serious answer is "why can’t she date all three, at least to figure out if there’s really an interest there.
My flippant answer to her (if I was a woman or my friend was a guy): “You know…I’m not too proud for sloppy seconds.” 
My other flippant answer (for her to say) would be:
“Number 3. Now serving…number 3.”
(This is my 100th post. Maybe if I didn’t spend so damned much time on this board, I could date one woman, to say nothing of three.
I’d also probably not be on probation at my job.)
'My serious answer is "why can’t she date all three, at least to figure out if there’s really an interest
there. ’
The men asked her out. Just because a guy asks a woman out, doesn’t mean she has to, or wants to, date him. IMHO, its quite easy to ask a woman out.
Why can’t she date all three? Because in this society, too many people assume that dating someone means sleeping with them. Thus, regardless of the reality, she’s afraid of appearing slutty.
What’s wrong with this picture?
According to the OP, she’s asked out by the first guy, and apparently puts him off, declining to accept or decline. Then within a week two more guys ask her out and she declines to accept with them as well.
She either doesn’t care for any of the three, or isn’t in a mood to date.
When she IS ready to date she should take them in order, when a guy asks her out she should decide rather quickly whether or not to accept the date. If she accepts and is asked out by someone else, she is certainly free to accept the new offer as well. But, she should decline the second offer if it conflicts with the first.
Cancelling a date with one guy to go out with another is a pretty low-class kind of thing to do.
I Am SouthernStyle
Back in my single days, I not only dated three guys at a time, I once had three dates in one evening (my personal record). It was great, what’s the problem? I was dating, not getting engaged. I liked all three, but I didn’t love them and they, I presume, did not love me. I did not have long-term monogamous plans with any of them, nor did they have such plans with me. There was no intimacy involved beyond simple good-night kisses. None of them were under the impression that I was dating them exclusively, nor did I think that of them. (Don’t know if they were seeing anyone else; didn’t care.) We went out, had tons of fun together, enjoyed each other’s company. Eventually I met another man in whom I did have deeper interest, and obviously that was the end of casual dating. But until such a time, there’s nothing wrong with going out with more than one person at once. Not every date has to be a quest to “find Mr. Right.” Not every relationship has to be aimed for a trip down the aisle. What’s wrong with dating someone you have fun with even if you know they are not your life’s mate?
You’re not very clear about what her problem is. She doesn’t like any of them? (She should turn them all down.) She likes them all? (She should limit herself to one per night.) She likes one more than the others, maybe? (Have a date with each, but be prepared to give up the other two if man #1 starts to develop as something more.) She doesn’t have three nights free? (She should lighten her schedule, no one should be busy all the time. Schedule one for next week if he doesn’t fit into this week.) Accepting a date with any one or all three doesn’t tie her to the person, and she doesn’t have to announce at the door, “You need to know that I have another date on Thursday!” Dating is a way to get to know someone better and hopefully have a good time, nothing more. If a first date leads to a second, then you can see what develops. A first date may also be the last if the two people just don’t click. If she sees more than one and eventually finds a deeper interest in one of them, she will know when it has reached a point where it would be appropriate to become “exclusive”. In the meantime, I recommend lightening up and being open to just getting to know people better and having fun along the way.