Update README with label sizes

README.md

@@ -14,3 +14,17 @@ Long term goal is to migrate and standardize on a universal, easy to use use ope
 - `//common` - generic labels
 - `//announcements` - public service announcements that only apply for a specific period of time
 - `**/OLD` - outdated/unused labels, kept for posterity
+
+## Label Sizes
+
+**Zebra - Large label**
+
+4x6 inches (100x152mm). Recommended 5mm margin.
+
+**Zebra - Medium label**
+
+TODO
+
+**DYMO - Small label**
+
+89x36mm. Recommended 5x3mm margins.