To do this instructable, first, you need an 8 foot long bat: https://www.instructables.com/id/Giant-Baseball-Bat/
2nd, you need access to a Vinyl Cutter
3rd, If you are going to charge for your services, you can't use a registered trademark without permission.
Instead of painting the logo on to it as I had planned, I was able to use the Vinyl Cutter that Tech Shop has and make a logo out of two colors for the bat.
This was the first try for me using the Vinyl Cutter -- I was a little worried that I would not be able to get the registration to work correctly and have everything line up, but it worked out fine.
Step 1: Get the Art Complete and Cut Out the Colors
The software that the drives the Vinyl Cutter only understands vectors.
Here is a link that shows the Vinyl Cutter doing its stuff: http://www.youtube.com/watch?v=NfulxCLyzSE
After you cut the vinyl, you need to "weed" it -- get all of the waste out of the rest of the "good" vinyl that will be used for the sign. You can use dentists tools to do this if the design is complex.
I cut an extra set of the black and the red layers just in case I screwed up applying the vinyl.
This project used about $5 of vinyl. It is very inexpensive.
Step 2: Apply a Transfer Film and Burnish It
After you weed the design, you apply the transfer film to the vinyl and then burnish it with the blue tool.
What this does is allow the adhesive on the film to "grab" the vinyl and when you are ready lift the vinyl off of the white paper backing.
If you look at the "Louisville Slugger" words, you can see how this works.
Step 3: Peel the Vinyl Off of the Backing Using the Transfer Film
After you apply the vinyl to the bat, you need to burnish it again so that the vinyl sticks to the bat when the transfer film is removed.
Notice that there are two black dots on either side of the words. The reason for this is that they are registration marks. The red circle has them too. This is how you get the vinyl to layout in the correct position.
Step 4: Affix the Second Color
After you have the postilion correct, burnish the vinyl and then remove the transfer sheet.
You can do this for as many colors as you wish.
Step 5: Enjoy
Make sure that you don't violate copyright issues. You can't charge for a trademarked logo.
Don't try to make the design too complex for your first attempt.
I had a blast doing this -- it was fun. I made it at Tech Shop.