I use some canned air and I view the carrier and negatives with the light at an angle (that way they "light up" and are easy to spot), works very well.
I do use a damp microfibre cloth on the enlarger, carrier and easel now and then though, to get rid of any stuck particles, then I blow before inserting the negatives.

I haven't cleaned my film backs yet though, thinking that any grit large enough to cause scratches must be visible and any dust particles will be washed away during development anyway. (but I probably should ).