A few tutorials, such as this one, utilize Porcelaine pens. I went for the oil-based paint Sharpies. I read that regular Sharpies didn't hold up with washing, so I went with the oil-based method. My mugs were picked up at the dollar store for $1/each.
Since I am not very artistic, I really felt the need to sketch my designs prior to going at it with the Sharpie. I did find that big Sharpie mistakes could easily be scratched off. Obviously the pencil didn't write great on the ceramic, but it gave me more confidence with my Sharpie tracing than free-hand. You could also use transfer paper to get designs going, but I wanted to save the money.
This took a LONG time. It was a meticulous design, but I actually got the inspiration from this Anthropologie mug. For the second mug, I printed a sketch blog "R" on card stock. I cut out the letter and traced it onto the mug. Definitely not as involved as the first. Also, beware where you hold the mug while drawing. My fingers wiped off some of the Sharpie a few times before I realized it. I do love how the design possibilities are endless!
That's it! I did let the mugs sit overnight before immediately putting them in the oven; however I'm not sure that was necessary. I totally dropped a mug while getting it out! It fell on the coils (but didn't break) and left a darker silver line through my "R." I just touched it up with Sharpie and baked it for another 10 minutes. Voila!
To be fair, I don't know how these will hold up through washing. Since they're gifts, I don't want to risk washing and having to completely re-do them. The mugs alone recommend hand washing, so I think they'll be fine with gentle hand washes. The Sharpie definitely stays to the touch after baking though.
I also added a sweet little touch to the mugs too :)