There are two steps to using this system: cloning and expression of the protein of interest as an ACP-tag or MCP-tag fusion, and labeling of the fusion protein using the SFP Synthase with the CoA substrate of choice. In this document, the labeling of fusion proteins with CoA substrates is described. The cloning of ACP-tag or MCP-tag protein fusions is described in the documentation supplied with the ACP-tag or the MCP-tag plasmids.