Before you start, check that the scene has an objective. You can be very precise about this: "I want X to discover fact y from source B" or just have a clear idea in your head that "John upsets Kate when he tells her about the date with Samantha." A useful technique can be to start pinning down a scene in a notebook with a phrase like "This scene is about Kate realizing that John is not as interested in her as she thinks." You can carry on quite consciously with something like "The scene takes place at..." The act of writing it down, making a sort of introduction, can often be a good kick start.
Come in late and leave early. This is a screen-writing golden rule and it applies to prose forms too. Consider this:
John walked up the path, rang the bell and waited for Kate to answer. Kate came to the door some minutes later. "Oh hello John." "Hello Kate. How are you?" "Oh fine, I guess. Do you want some coffee?" "Yes please!"
This gets no-one anywhere, least not Kate and John who have big stuff to discuss. It would be better to begin with something like this:
"I saw Samantha last night," John said. Kate almost spilt the coffee down the front of her dressing-gown.
A lot of contemporary fiction suffers from endless driving. I suppose it is part of the culture, but when there is transport involved something ought to be happening, not merely getting characters from scene A to scene B. If you find your characters spend hours getting in and out of cars, and worse still braking or changing gear, or parking for no real reason, get out the red pencil.
Combine scene functions for maximum impact and interest. Can the car chase to catch the bad guy also reveal the heroine's agoraphobia?
Don't describe everything. Think in terms of cinema.
Make each individual scene as interesting and dramatic as possible. If the setting or the set up is ho-hum you won't even enjoy writing it. Consider those police briefing scenes in detective stories when everyone gets up to date on what they know about the case. This usually involves a load of cops in a room with a notice-board. Usually one officer gets one piece of information to put over, and it's up to the writer to present each character in turn in an interesting and involving way so that the information is put across painlessly. Think of a fresh way of doing a police briefing scene.