Adjusting patterns to fit your need

 So last week I shared a free pattern for a baby romper. The catch? It was size Newborn (so up to 8 pounds?) So I thought I would share how to alter the pattern to fit your needs. Really you could alter the pattern to be any size you like with these tips. Also learning how and what to alter can help you alter other patterns as well. So to start things off here is a common question I get:
Can I enlarge the pattern to make it a larger size? The answer? No. If only it was as easy as printing the pattern larger, or blowing it up in a copier. The truth is that not all places of the pattern grow when going up a size. You only add space/length to a pattern where the child grows. So let's get started.

 With the leg of the romper you can follow the crotch line down and add length to the bottom of the leg which will lengthen the leg room since kids grow taller. Also I would add width to the leg so the fit is more comfortable around the leg. To determine the amount of length you should add measure the length of the pattern (subtract seam allowance from top and bottom and typically hem allowance the this pattern has a cuff so you can skip that) Then measure the child from the crotch to the bottom of the leg to decide how much you need to add to the bottom.

 Adding width is the most important through the chest area since that is another place kids grow. Simply bump out the chest line just at the under arm. Then you will likely want to add length in the chest or torso area as well. This can be done one of two ways, you can simply cut across the bodice and add an inch or two to make it longer, or you can add some length at the top of the pattern.
What to choose? If you are only going up a size or two you could likely get away with adding to the top only, if you are going up several sizes you will want to add room in the torso area as well. For all sizes you will want to add width in the chest.

 The line that follows from the crotch to the top should not be altered. The needed width was added to the other side and you don't need to change that line, except maybe making it longer when you add the height in the top or torso.

 You also want to be careful to carry over any marking that the pattern has adjusting them as needed, for example the romper has the leg facing line, and the cut line at the top for the back of the pattern.

 A little tip if you are altering the length and are not able to measure, or unsure about the measurement. Grab a pair of pants that fit well and fold them in half so the crotch seam and leg line are exposed. Then trace the length.

 A few other things, You will want to add length to the shoulder straps (you can always guess and trim it back if needed) also you will want to add width to the cuff. For that simply wrap the cuff around the ankle, (keep in mind the pieces overlap, and you need to subtract seam allowance) then you can add as much width as needed.

 Next, some key pieces that need a little altering. The facing and the back panel. You need to add some width so they fit properly across the chest and back.

So add the width you need along the fold line is easy. Also be sure to add any height to the pattern piece that you may have added to the front and back piece.

Then you are good to go. The pattern is altered and ready to sew in any size. You can use many of these same tips in adding room where your child has grown (compared to the pattern piece) to alter any pattern you need, all you need is a pretty good understanding of how the pattern goes together and what the pieces are for.

Hopefully that helps!