To sign "crosswalk" I recommend you first show STREET (note that in
my example I topicalize the "STREET" sign by raising my eyebrows a
bit), then use a CL-C (classifier C) to show a "section" of the
street going crosswise. Next use a CL:V to show a person "walking"
along that section of the street.
You can learn
American Sign Language (ASL) online at American Sign Language University ™
ASL resources by Lifeprint.com © Dr. William Vicars