I just got the Unimold starter kit - I have read the guide showing the process but am a bit unsure of the process between the coupling coat and the final reinforcement layup. Before laying up the final reinforcement Do you 1. Allow the coupling coat to completely cure. 2. Allow the coupling coat to tack, or 3. Apply the final layers immediately over the wet coupling layers.

In the PDF instructions it says to leave the initial gel coat overnight to cure before the coupling coat is applied but in the video for the car bonnet part 1 using Unimold it states to wait a few hours. Which is correct?