How to keep the stove top clean?

Depends on the type of stove top you have.

For most of us who have NON Stainless Steel (so far) here are two tips:

After cleaning, try using a cap or so full of white vinegar and 2 day old news paper (the ink will be too new if the paper is hot off the press!). Apply the vinegar directly onto the newspaper and buff off with the dry portion. The ink from the paper will add a bit of a shine! - you can also try windex but vinegar is much cheaper ;)

Apply a small amount of car wax to the top of the cooker (you can also do this with tile, ceramic sinks and anything that may have a tendency to attract dirt). Make sure it's clean to start and not hot. Be careful not to apply it to the hob or flame area but just OUTSIDE the cooking area. The end result will help things to not stick to the surface of the common enamel cook top.

About the only way to keep the stove top clean is to clean it very good every time you use it. This will help keep the grease splatters off. Another way to keep it clean would be to put foil over the whole top and cut out just enough for the burners. Not the most pretty site but it does keep the top clean. If you are going to have visitors over you could just remove the foil and then put it back when the visitors are gone. This also works good in your oven when you are cooking something that runs over. Instead of it running on to the oven it will run on to the foil and you can take the foil out and discard it and put a new piece in for the next time. The foil will save you a lot of time and a lot of hard scrubbing. I am sure you have better things to do than scrub on a stove top or oven all day.

I clean my stove everyday. I just spray and wipe it down.