Playing around with bokeh again.
I know this is a bit of a cliche but I was intrigued to see if it would work.
First off you need a relatively fast lens, I used my trusty Canon EF 50mm f/1.8mm.
To make the hearts (or any simple shape) you then need to make a “hood” to cover then end of the lens, I made mine out of plain black card. I then cut out the heart shape in the middle, make sure the actual size is < about 20mm, (there is a rule to do with focal lengths governing this but I can’t remember it). I’ve enclosed a pic below of the one I made :)
Open the aperture as wide as possible and find any point source of light for the background (I used chrissy lights), focus on something close to the lens and snap away.
There is a decent tute here if you need further info