During Victorian times, women covered their head during the day with day caps of lace, ribbons, and trim. The look was low and wide with more decoration on the sides than top.
"For at-home wear, the lady wore a cap of lace and ribbons with
little lappets coming down the sides of the face like
a spaniel's ears (which was, coincidentally, the most popular breed of dog at this time).
These caps were charming in the extreme."
Victorian women would instantly know the difference between a doily and a day cap. Unless you plan on balancing tea upon your head, don't wear a doily, make yourself a day cap!
For more historical look, use natural fibers like cotton and silk instead of polyester ribbons and lace. Extant caps are often very, very fine and soft, think thin batiste cotton or fine net like base instead of quilting cotton fabric base. The one below is much better than a doily and leaves a nice border of trim peeking out from a bonnet, but wouldn't pass as an extant cap.
Draw a half circle with a radius of 6". The front will be the flat side. Fold in half and then half again. Near or along these fold lines, make 2.5" long x 1"-1.5" wide darts on the back and back sides. Draw some cute 6.5" ears and add them on.
Cut out lace or cutout backing fabric and lace/net overlay.
Sew lace overlay onto fabric
Stitch darts and then iron or fold them towards the center.
Sew lace/trim around outside. This example has wider lace on the back.
Add more lace being careful to go around the curves of the fabric/darts. You may find it easier to pin the lace on while the cap is on a styrofoam head or some other round head sized object. Hurrah! A use for all those favorite scraps of lace you've been saving.
Add ribbons. Add ribbons ties at the ends of the half circle underneath the ears. If you don't want ribbon ties, you may want to add loops on the bottom for bobby pins or sew in a few hair combs.
Finished reproduction 1840s day cap looks like this. If this style originated in
1840s, probably younger women wore it first, then older women might be wearing it in later years (or same woman wearing the cap 10 years later
like your mom or grandmother wearing yesterday's fashions).
Synthetic black and white lace and ribbons over cotton fabric.