1) Import your RAW files into LR. Select all images from the gallery that will need to be edited.
2) Navigate to FILE > EXPORT AS CATALOG...
3) Give the Catalog a name. Make sure ONLY the box "BUILD / INCLUDE SMART PREVIEWS" is selected
4) Wait until the progress bar in LR has fully completed. The process will take anywhere between 20min & a couple of hours.
5) Quit Lightroom
6) Find the Catalog you created, and send us both the .lrcat AND Smart Previews.lrdata files
You can view our video below for a visual step-by-step guide: