How do I get this 4-bit synchronous up/down binary counter to work?
This shows all the info you need for a truth table.

74HC' Ron driver resistance is approx 50 ohms at 5V to estimate your LED current, add suitable R for current limit. eg if Blue = 3V , then 2Vdrop/10mA=200 Ohm, so use 150 ohms. then verify voltage drop on R=150 = 1.5V. thus Voh =4.5V.  (for example).

Include cap across Vss to Vdd for 5V and twisted pair for Clk //Gnd if using long wires.


Observe LED cathode towards gnd.  (-ve is always the reflector cup side and may have marking (flat edge on body)





Never leave CMOS input floating.  Pullup 1M to 10k.
Beware of ESD damage.