So after you have purchased your pattern and the materials needed for your project as listed on the back of the pattern envelope, you are ready to cut out your pattern pieces and fabric!
First, you will open up your envelope and take out the instruction sheets. On page #1, you will find which pattern pieces (they are numbered) for the different styles in the envelope. Let's say you are making "View A". Go to the bottom of page 1, and it should list which pattern pieces you will need. (see below)
I made the jumper which is View A, so I needed pattern pieces for the jumper, contrast band and interfacing. I noted the numbers I needed and then I opened up the pattern pieces and found what I needed.
You should know by now what size you plan on making. I was making a size 6 but the pattern included several different sizes. I would suggest committing to a size and then cut that size out of your pattern. If you need another size for another child, I would buy another pattern especially when you can get them for 99 cents.
Go ahead and cut out your pattern pieces on the lines that has the size you want on it. If your pattern pieces are really wrinkled from being in the envelope, you can iron them...just remember to turn the steam off first. =)
Before laying your pattern pieces on your fabric, go ahead and read the "General Directions" section which is at the top of page 1. This section will tell you how to fold your fabric to cut your pattern pieces out. Most patterns say to fold your fabric with the right sides on the INSIDE. This is opposite of how your fabric comes.
Now go back to the bottom of page 1 and view A in my example (see picture #1 above). Here they show you how to lay out your pattern pieces to get the most out of your fabric. Normally I do try to follow what they have down but there are some instances when I find a better way to layout what fabric I have. Here is my jumper laid out on my fabric:
It will say right on the pattern piece how many you need to cut out and if one edge needs to be on a fold. All of my jumper pieces needed to have one side on a folded edge. There is a double arrow on the pattern which indicates this: (Can you see the double arrow on piece #3?)
Once they are all laid out, go ahead and pin your pattern pieces to your fabric. You don't need a ton of pins...just enough to hold the patterns in place. Some folks even use pattern weights to hold down the pattern pieces while they cut. When cutting, do pay attention to certain markings. There might be some triangles in your pattern pieces. The pattern writer wants you to cut outward notches at these markings. If you forget to do so, like I often do, then you can use a fabric pencil to mark where they should be on your fabric.
When you are done cutting, you can take some of the pins out but I would leave your pattern piece pinned to the fabric. The pattern will refer to them by number and name, and it will be easier to identify which piece you will need if the pattern is still attached.
So hopefully that will help you get started with sewing with commercial patterns. If you struggle initially with them, don't fret...most folks do struggle at first. Just grab a cup of hot chocolate and take the pattern one step at a time. =)