It looks like a bulb that size and shape isn't a good match for that can (or at least the ring), since it doesn't give you a simple way to grab it for replacement. One way to grab the bulb is with a suction-type bulb changer, like this:
They're designed for changing bulbs without a ladder. The suction head is normally mounted on a sufficiently long pole to reach the bulb. Different size and shape suction cups are available for different types of bulbs. This example is for floodlight bulbs. You push the suction cup against the bulb. It grabs firmly enough to screw the bulb in or out. The cable on the side is to break the suction and release the tool.
If the can is easily accessible, you could just try wearing rubber gloves, or gloves with rubber dots or lines on them. Pressing against the face of the bulb may give you enough friction to twist it.
BTW, there is bulb lubricant that makes it easier to get bulbs in and out. It's some type of non-insulating grease that you put on the threads. I've never used it, but some people swear by it for hard to access bulbs.