Normally in bed, start watching then copy what is happening on n the screen
The last thing I watched with a partner was Suicide Girls Italian Villa (https://www.lovehoney.co.uk/product.cfm?p=14628) on DVD on an XBox in our lounge.
My wife loves it when I watch porn while we have sex, she loves it when we do doggy style so we can both watch...... Leads to some of the best orgasms
My boyfriend and I usually watch it together, touching each other. And then we go for a ride. Porn can be a type of foreplay. Remember communication is key and always use lost of lube.