So I work for a sign company and having problems creating Pantone and Sherwin William colors. The monitor shows the color but printing is no where near where I need to be. So I have to mix and match and play with it.... is there an easier way?
There is a far more accurate and intelligent way, but I don't know that I would characterize it as entirely 'easier'. Many RIP software products (you don't mention which RIP you are using), and popular design programs already contain references to Pantone PMS colors in them. Most of these same RIPs also allow users to create their own 'custom' colors, which can be any name that the user desires, including Sherwin Williams colors in your scenario. You would need a physical specimen of the custom color to measure from.
There are two 'gotchas' to this:
1. You would need a spot color measurement device to obtain an accurate definition of the sample. A spectrophotometer such as an i1 is very widely used, and a new group of less expensive measurement instruments are now coming into the market. I am referring to the Swatchmate Cube, and the Nix Color Sensor, among others. The device should be able to define the color using LAB color model for best results.
2. You would need a design application that gives you the ability to define custom spot colors. Adobe Illustrator is one such design tool, but there are others I am reasonably sure.
Using a file format like EPS or PDF, the RIP could be configured to parse and look for the named spot color, and assuming that it finds it, it will rely on the ICC profile for the media in question to attempt to reproduce the reference color as closely as possible, within the gamut limitations that are imposed on us all in the world of digital print. A custom-built media profile that includes an accurate ICC profile will yield the most accurate simulation possible of the reference (Pantone or Sherwin Williams paint in this case) color.