When to finish before assembly
Most of us apply linear thinking to project building: Cut parts to size, fasten them together, and then apply finish. But good woodworkers don't always finish last. In some cases, it makes sense to apply finish before you glue parts together.
For example, in the assembly shown right, the spindles will be less than 1" apart after being joined to the rails. Brushing on the stain (and later, the topcoat) before glue-up gives you easy access to all sides of the spindles, as well as the full edges of the rails, and avoids uneven coloring from stain stuck in confined places. Painter's tape keeps finish off the tenons, preserving a clean surface for glue-up.