Is there something better?
 

I am in charge of the guest book for a baby shower, along with the quilt top. My idea is to have each guest sign a charm size piece of fabric to later be put together for the backing on the quilt. The charm pack I purchased is from the same line of fabrics being used in the quilt top. I was thinking of using sharpie markers for the pens. Or is there something better to use? Thanks You!

I've seen this tutorial and always thought that it is a cute idea for a shower.

Just make sure you get good quality spray (and use it outside)!

I keep hearing that sharpies fade very quickly I can't not remember the name of the better choice. But I'm pretty sure you can buy them at Joanns or your LQS.

Is the quilt intended to be used or a decoration for the room? Baby quilts get washed more than the average quilt I don't know if any pen would hold up to that kind of love.

I remembered Its micron pigma pens.

Also quite a while ago someone did a pen experiment and posted the results I searched for it but came up empty but maybe you can find it. I'm pretty sure it was in the general section.

Use Pigma Pens instead.

I've used Pigma pens also for wedding quilt squares. And it helps to have freezer paper on the back to make it easier for people to write on the fabric.

I have ONLY and always used Pigma pens. You can normally find them at JAF

Sharpies bleed/fuzz around the edges. Permanent micron pigma pens are fade resistant and create a nice, clear, smooth line. Press freezer paper to the back of the squares for stability and draw a pencil line 1/2" inside the square to give the guests a guide (otherwise some people will write from edge to edge and some writing will be lost in the seam allowance)

As ckcowl said, make sure to mark the seam allowances prominently. There have been many posts on here about shower quilts that have gone awry due to people writing in the seam allowances.

Ugh! I agree! I mistakenly did this at a wedding once and made note of it in front of others signing squares of fabrics. They questioned why I was upset and muttering in whispers to myself (these are all non-sewing relatives). I told them being a quilter I should have thought of staying within a boundary BEFORE I started rambling my heartfelt message to the bride and groom on a small piece of fabric, knowing it was going into an heirloom memory. We used fine line Sharpies, but I believe it was going to be a wall-hanging, not a quilt.

Definitely Pigma pens and not sharpies. Freezer paper a must too. If you don't want to mark the seam allowance on all the squares make a few templates that can be placed over the squares and have the person write in the blank space.