Basic idea of how it works here is a system we have called "line bidding"

We get somewhere around the first or second week of each month a "bid packet" which will have somewhere around 100 pre-built lines. Each line is made up of trips or pairings or whatever you want to call them. After the lines are the "pairings" or what each pairing actually is. In the lines you will see something like N1234. If you scroll down and find N1234 it will tell you exactly what that means, such as a 4 day with overnights in X, Y and Z and it starts at this time and ends at that time.

All the lines tell you is which days you will work, how many days off, how many hours away from base, how much you will fly and what it will pay you. It is the pairings below that tells you exactly what it is.

We have until around the 15th or so of each month to make our choices and arrange those lines in order of how we would like it to turn out.

As a new guy you can assure nothing. You will of course make all your choices like everyone else but will end up with whatever nobody wanted by the time they reach your seniority. As a junior pilot you will have no control over what you fly each month and it will usually be reserve.

If you are number one, you simply look at the lines, pick out exactly what you want and bid for it. You are guaranteed that line being number 1. It gets trickier as you work down the seniority.