Water-based gilding glue takes around 20 minutes to come to tack - i.e. to be ready for the gold leaf that it inevitably will be gilded with. After this, the glue will be available for tacking and gilding for the next 30 hours or so, providing a long enough window to get the job done. This means that, even if the process gets to you the first time, you can always come back to it with a clear head.