What is the easiest way to paint on wood to make signs
Use a stencil. Then when finished spray with Lacquer to seal.
Here is how I made a welcome sign for my porch: https://thehoneycombhome.com/diy-wooden-sign-for-the-porch/
Ideas from other Hometalkers.
OMGosh the fastest way is to use a roller pattern - here is a YouTube video on the process - https://www.youtube.com/watch?v=oXc_tB7eAUw
and a blog post - https://www.artisticpaintingstudio.com/blog/decorative-signs-stenciling-techniques/