One issue all woodworkers face is how to remove all of the sawdust from the surfaces of their project before they begin the finishing procedure. No matter whether you plan to paint, stain or apply natural oils as the finish on your woodworking project, you'll still need to remove even the finest grains of sawdust and sandpaper grit before you begin the finish. Without removal of as much sawdust as possible, some of the remaining sawdust can get mixed in with the finish, causing a variety of potential issues dependent upon the amount of sawdust that remains.
I typically begin by blowing off the project using an air compressor hose or using a shop vacuum to clean as much as possible. This will help to get the sawdust out of all of the nooks and crannies within joints on the project. I'll then follow-up with a wipe-down using a dry, clean cloth and then a tack cloth or two, but sometimes even the tack cloth won't remove all of the residue.
One final step I like to employ is to use a clean cloth with denatured alcohol. The denatured alcohol will help pick up even the finest dust and since it evaporates very quickly, it will not discolor the wood in any way. It is even safe to use on projects that will be used for food, such as a cutting board or hardwood bread tray.