HOW DO I USE A PUSH BUTTON TO TURN ON AND OFF A RELAY CONNECTED TO PIC16F877A

I have been having troubles doing the above topic and i will love if you guys can help me out.

I started programming few weeks back. I want to design a switch in which when the push button is pressed, my fan will ON, and when i need to turn it of, i press the same push button. so here is my code below.

#define OUTPUT 0
#define INPUT 1
#define ON 1
#define OFF 0
#define SWITCH1 PORTC.F0

#define LED1 PORTD.F0

void main() {

TRISC=INPUT;    TRISD=OUTPUT;
PORTC=OFF;       PORTD=OFF;

while(1){
if(SWITCH1==ON){
delay_ms(100);
if(SWITCH1==ON){
LED1=ON;
delay_ms(100);
}           }

if(SWITCH1==ON)
{
delay_ms(100);
if(SWITCH1==ON){
LED1=OFF;
delay_ms(100);
}          }

}

I will love to hear response from my fellow programmers. Thanks