TOPIC: varnishing advice?

So I'm near the end of my varnishing coats on my Crosby Capri. I haven't paid a ton of attention to the layering coats knowing I was just going to sand them down. As I'm getting closer, on these last couple coats (before the final) I'm pretending it's the last coat and not have any imperfections. All I have to say is I'm glad it's not my last coat and I'm about ready to slit my throat. I finished up the benches last night in hopes that it would the final coat on those before I hit the boat itself. I blew them off thoroughly with my compressor, then wiped them down twice with Epiphanes thinner, then hit them with a tack cloth. When I checked them after they dried the finish looked great (using Epiphanes varnish) but there were a ton of tiny dust particles in it that I didn't see when I was alying it on. I'm in an enclosed garage that I swept before I varnished (the benches are on the garage floor). I'm still using cheap foam brushes until the final coat. Could that be the problem? I didn't have a drop cloth under them either. Could stepping around them on what I think to be a dust-free floor be kicking up dust that settles on the benches? Any ideas?

Brian