Originally Posted by AdelaaR

There are some fit calculators on the net that can get you a pretty good fit and they are free.
When I got my first race bike a few weeks ago I used the one at Competitive Cyclist.
You'll need someone to help you measure up and after you put in all your measurements it will output good fit numbers for your bike.
With the help of that I was able to set it up well enough even before my first ride on it.
Setting the saddle too low is a typical newbie mistake, btw ... don't worry ... you'll learn