I use a fine mechanical pencil on light colors, pressing just hard enough to leave a light line. On darks, I use a washable colored pencil in a color that closely matches the background, but can still be seen.

Annie

best marking pencil I've found for colors is Nonce. It's white and waxy and washes out easily with a damp cloth.

Here is a link that might be useful: Nonce pencils

Crayola washable markers.

Far and away, my favorite marking tool for straight lines on any fabric is a Hera Marker. It is a piece of plastic with an edge that makes a tiny crease. You can use it before or after basting; I prefer BEFORE for better accuracy. Get the fat ROUNDED one (link below), much easier to use than the pointy slim one. If you make a mistake, simply dampen the fabric and remark again when it gets dry. I use it for other sewing, too; general placement lines for applique, to mark for seams, cutting lines, or alterations.
If you have trouble seeing the line to quilt, simply change your angle of light.
Sometimes I use a fine point blue washable marker, knowing that I CANNOT leave it in the car, or expose it to ANY heat, and that it will have to be rinsed out with plain cold water later.
On dark fabrics, I like to use a White Berol Pencil. With a lot of handling, like on a border that gets quilted last, it can rub off, so sometimes I will need to go over it again later.
Recently I have also tried the Clover White Fine Point Pen that is removed with water or heat. But IMHO, it is expensive and does not cover a lot of territory before it runs out or dries up in storage. It is a new product  who knows what these chemicals will do over the years?
The worst tool you can use is yellow; I've heard horror stories about yellow markers either not coming out, or re-appearing years later or after washing.
BlueBars

Here is a link that might be useful: Hera Marker

I ordered an Ultimate Pounce thingy just now. I was going to try Glad Press-n-Seal and draw right on it, but I read someone's comment that it didn't tear out so easily and left tiny pieces that were near impossible to get out.

They also commented that the Press-n-Seal Freezer was light blue, and heavier. They used it to make stencils for pouncing
just by printing a pattern on paper, apply PnS Freezer, using machine without thread to "sew" along the line making a row of holes. Transfer the PnS Freezer to fabric, and pounce away. She said it was okay to link, so I put the page below.

Sounds neat, and above all for me this time of year, CHEAP.

Here is a link that might be useful: antiquequiltlover's PnS stencil method

another woman out there in cyberland gives another idea-

Lay a piece of bridal illusion, very fine netting, over the pattern and trace it with a Washable Crayola Marker. Then lay the bridal illusion over the fabric, and trace it again using a Washable Crayola Marker (or other marker of your choice, I presume.) I'd be sure to test this one! And not use yellow!

I try not to quilt on anything that won't take the thick
washable blue pen, ie, darkcolors :)
I love them because they consistantly come out & they are so easy to use with a stencil. The thicker line is great for my aging eyeballs. Jill

What a great discussion. You gals have mentioned products I have never heard of. I am particularily interested in the press'n seal stencil. Thanks for sharing all of your methods.
Jean

I've used the Glad Press 'n' Seal wrap. Yes, you can use a marker to draw your pattern on it. It will stick, with just hand pressing, to your fabric. I was so hopeful that I would love it.

BUT, it's an absolute bear (please read other bad words here) to remove. I would never, ever recommend it. I was picking out pieces of that stuff for months from just a small quilt.

So not worth it.

I use the Bohin mechanical chalk pencils. The "leads" are very fine and you can get them in different colors. They're actually chalk, so they wash off very easily!

Anjea

Here is a link that might be useful: Bohin Mechanical Pencil

I just ordered the Bohin with the fine chalk but have 2 of the older ones with the thicker chalk. They work just fine for tracing around templates or cookie cutters. I also use the Crayola or RoseArt washable markers. I've never had a problem with them washing out regardless of the color.

Always test everything before using it on your quilt.
I tried the PressNSeal for hand quilting some floral designs. To draw the design onto the PNS, I tried ballpoint pen, Sharpie pen, and also some of the lighter color markers. The problem I had, even though I let them all dry for 48 hours first, the color of the marker kept rubbing off onto my thread. The thread got darker and darker. When I took it out, there were dots on the fabric.
Using it as a stencil might work with removable markers, but I'm not sure if chalk would stay on the fabric when you pull off the PNS?
BlueBars

Rather than Press n Seal to make moveable stencils for pouncing, I use lightweight template plastic. I draw the design with a fine-point permanent marker, sew around it with a dull needle in my sewing machine and then use double-stick tape to hold it in place. I make a pad from some old batting and use baby powder to pounce the design. The baby powder does brush off very easily so this method works best on small simple designs.

Annie

I never heard of using Crayola Washable Markers. WOW I'm going to share the idea with my quilting pals. I know none of them have tried it either. Think I'll try the bridal Illusion idea, I have a small multi colored quilt and have been trying to decide how to mark it. No wonder this is my favorite place to visit.

I was bound and determined to use that Press n Seal, seeing how I'd already bought it. I marked with a chalk pencil, and put strips or squares of PnS over the marks to protect the chalk. It's on a Q-snap type of frame, and I'm going to take off just one piece of PnS when I'm ready to quilt that part.

My question is are the Crayola washable markers just the kind you find in the kids department or something special for quilting? It's a new concept for me. I have always bought the making pens use with quilting but find they often dry up before I use them up.
Jayne

I have also noticed that the marking pens I have gotten at the quilt store dry up too fast. Are the crayola ones thin enough for fine marking?

i use crayolas too. (even tho i am still a lowly stitch in the ditch machine quilter) just the ones i can scavenge from the bot's secret stash (he hates it when i steal his markers) just regular old markers. I haven't had any problems with wash out or bleeding. the mini fine tips i find better than the big 'little kid' fat markers.

and they come in oodles of colours so you can either contrast or match for colour.