Yeah, there are several things that will improve your soldering that have nothing to do with skill.
- Good solder
- A good tip
- Everything else
And I'm not really sure about the order of 1 and 2.
If the question involves cleaning other than removing excess solder and oxidised flux, I'd think about whether it was time for a new tip.
As
@kellys_eye says, a new tip can make a huge difference. And arguably, if it does, you should have changed it earlier.
Back in the old days when tips were copper rods filed to shape, filing your tip was something you might do routinely to refresh it. With the change to coated tips, and the use of coatings not soluble in tin (copper will dissolve in tin) means that filling is not only unnecessary, but destructive.
Incidentally, I may be in a similar position to you in that I have (at my local hackerspace) a heap of donated soldering irons with tips that melt solder, but where it just drips off without wetting the tip. I think the real solution is new tips, but I'm happy to try sal ammoniac (ammonium chloride) or even a file (someone has already tried steel wool).
Hopefully, by the time I return, someone will have found a source of new tips.