If you are personalising a guitar, one way to customise it is to make your own logo decal and apply it to the headstock of the guitar. The headstock is usually where the logo is for the company that made the guitar. If you have the right materials, you can design your own logo decal the way you want it and make it look like you bought it that way. This is also helpful if you make your own guitars.
Measure the area with a ruler where you want to place the logo decal to determine how large the decal needs to be.
Open a graphic editing program (see Resources) and create a new document with the dimensions that you determined in step 1, in inches or centimetres.
Design your logo on the new document by adding text with the text tool, drawing designs with the paintbrush or by downloading a free clip art image and sizing it to the document. Go to "Image," "Flip Horizontal" to reverse the image like a mirror.
Load your laser printer with printable transparency paper and print out the logo you designed. Cut the logo out with a pair of scissors and leave about 1/4 inch of the transparency around the edges of the design.
Spray a thin layer of spray adhesive on the area of the headstock where you want to apply the logo and spray a thin layer on the back of the logo itself. Wait 10 seconds, stick the logo to the headstock and smooth the logo out gently to remove any air bubbles. Wipe away any excess adhesive around the outsides edges of the logo with lighter fluid and the tip of a rag.
Apply a thin layer of clear lacquer over the logo and let it dry. Keep adding layers of lacquer until the edges of the transparency disappear.