Circuit elements can be styled using Matplotlib colors, line-styles, and line widths.

Resistor circle

Uses named colors in a loop.

with schemdraw.Drawing() as d:
    for i, color in enumerate(['red', 'orange', 'yellow', 'yellowgreen', 'green', 'blue', 'indigo', 'violet']):
        d += elm.Resistor().theta(45*i+20).color(color).label('R{}'.format(i))


And for a change of pace, activate Matplotlib’s XKCD mode for “hand-drawn” look!

import matplotlib.pyplot as plt

with schemdraw.Drawing() as d:
    d += (op := elm.Opamp(leads=True))
    d += elm.Line().down().at(op.in2).length(d.unit/4)
    d += elm.Ground(lead=False)
    d += (Rin := elm.Resistor().at(op.in1).left().idot().label('$R_{in}$', loc='bot').label('$v_{in}$', loc='left'))
    d += elm.Line().up().at(op.in1).length(d.unit/2)
    d += elm.Resistor().tox(op.out).label('$R_f$')
    d += elm.Line().toy(op.out).dot()
    d += elm.Line().right().at(op.out).length(d.unit/4).label('$v_{o}$', loc='right')