Dust is my enemy [>:]

After doing the sanding bit as mentioned above the dust hangs in the air and settles on the paint I am applying, leaving myriads of lil specks.

Even if I go into another room to apply the paint, I still get specks !!

And I have tried different brushes and paints, Japlac seemingly less prone to specks of dust spoiling the finish, but it still gets them.

Any clever ideas folks ?