Was replacing a light switch in our powder room when light in the kitchen turned off. I might have a short circuit and tripped circuit breaker. So, checked my circuit breaker panel, but nothing is in the "off" position. Reset the circuit breaker anyway, by turning all switch to "off" and " on" again (including the main switch), but still no power. Any suggestion, please.

Describe the wires in the switch box.

Describe the wires in the switch box.
We have an old house, the switch has 4 black wires.

Look closely, two should be white and two should be black.

If wiring really old might be hard to tell. Two should be in one cable and the other two should be in other cable.

By wires do you mean cables? A wire is a single wire. A cable is two or more wires in an outer covering.

By wires do you mean cables? A wire is a single wire. A cable is two or more wires in an outer covering.
Since its too old, I looks all black to me, but wires, hard thick ones. After I reset the c. breaker and the light didn't turn on, I didn't continue with the installation, thinking this is what is causing the problem, I just put elect tape and made sure they were separated... then, tried to reset the breaker again, but still no power, kitchen light, powder room light, microwave, and porch light & outlet.

Problem is not the breakers. Problem is in the wiring in the switch box.

Tell me if you mean 4 wires or 4 cables. You should have had two wire connected to the switch. Other wire should have been connected together. What did you find and what did you do.

Since its too old, I looks all black to me, but wires, hard thick ones. After I reset the c. breaker and the light didn't turn on, I didn't continue with the installation, thinking this is what is causing the problem, I just put elect tape and made sure they were separated... then, tried to reset the breaker again, but still no power, kitchen light, powder room light, microwave, and porch light & outlet.
My main concern tonight is how to put the power back on. Does leaving the wires open affect the resetting of the circuit breaker? This is my mom's house and I'm just helping her out, but I guess I'm not at all helping. What else can I do to properly reset the c. breaker and have power?

Only way is to reconnect the wires.

Only way is to reconnect the wires.

Oh OK, it's too dark here, wish I could send you a pix, of the wire, the switch I was replacing and the replacement. I guess I'm going to check it again tomorrow. But what I did is, put the wires in the exact position where they were in the old switch. Thanks for your help.