My boyfriend and I have been camming together for about 2 and a half years now and this is some advice I can think about right now...
1.- Planning. Both make a schedule with B, C, and D plans included, that way you won't get lost in the void just thinking what to do next. This part includes thinking about how to set your camera/lights so both look good all the time and/or show what you really want to show and the way you want it.
2.- Teamwork. Be sure that both are having fun, feeling good, and participating. I find it super depressing when there's just one part of the couple participating, smiling, talking to viewers when the other person is just yawning and clearly in Jupiter. Make sure you both feel good all the time, do not sacrifice your good mood to please viewers.
3.- Awkward silence: Even if you have luck, many viewers and your goal is about to be reached, there are gonna be moments when u lack tippers, no chatters, kinda a cemetery. At first, it was really upsetting but my boyfriend and I realized that we should have fun or some rest during the nothingness.
4.- Pressure to be "perfect", it links to the third point and you might know this already since u are a performer. Do not try to look super horny, sexual and/or perfect all the time, I mean... if you are alone is way easier 'cause you know your limits but if you are with someone, you should be aware that she/he is not comfortable and is faking a smile/position just to look appealing for viewers and believe it or not it has caused arguments between my boyfriend and me.
5.- Enjoy yourselves, at the end of the stream you are a couple and business might not interfere in your relationship.
I can't think about more advices xD
Break a leg