Well… everything may becomes boring when you do it same way every time. Sex is not an exception. Try different things that will bring in excitement not boredom. If you only do it in the bedroom at night, why not start kissing from the sitting room then kissing till you get to the bedroom and then…?
For the man, you can interrupt her once in a while while she is cooking and you know…
For the woman, you can pull him back while he is dressed for work and do something silly.
Things like this brings excitement.
Don’t just be restricted to same sex routine… explore!