When you've got all of the footprints assigned, run pcbnew, the board layout editor.

Setup

For some of the design rule settings, see: https://docs.oshpark.com/design-tools/kicad/kicad-design-rules/

File→Page Settings 

  US Letter
  issue date, revision, title, company, comments

Setup→Layers 

two layers
thickness 0.062

Setup→Text and Drawings 

set to nice round numbers close to the defaults; see figure

Setup→Mask Clearance 

Solder Mask Clearance: 0.002

Setup→Design Rules 

     Global Design Rules  (for oshpark)
     	      minimum track width: 0.008
      minimum via diameter: 0.008
      minimum via drill: 0.015
     	      Custom Track Widths:  add some handy ones
      	     0.010
	     0.020
	     0.040

Net Classes Editor 

    Clearance:	0.008
    Track Width: 0.008
    Via Dia: 0.030
    Via Drill: 0.015
    uVia Dia, Drill: same as via
    Diff pair width: 0.008  (doesn't really matter)
    Diff pair gap: 0.008

Load your netlist

position parts

route the board

DRC check

adjust silkscreen positions

add additional text

DRC check

export gerbers