A Lot of Confusion in Writing My First Library

(The sketch that I want to use the custom library in)

//----------LIBRARIES----------//
#include <TimeLib.h> //Used by the alarm system. Might have to delete this as a duplicate?
#include <TimeAlarms.h> //Used by the alarm system. Might have to delete this as a duplicate?
#include <DHT.h>

//----------CONSTANTS----------//
#define DHTPIN 2 //Data pin from the sensor connects to Arduino pin# 2.
#define DHTTYPE DHT11 //DHT 11 (AM2302)
DHT dht(DHTPIN, DHTTYPE); //Initializes the DHT sensor for normal 16mhz Arduinos.

//----------GLOBAL VARIABLES----------//
int temperature = 0; //Used by the temperature sensor. Real-time temperature data (F).

int chk;
float hum; //Stores humidity value.
float temp; //Stores temperature value.

const int InlineFan = 13; //Names Arduino pin# 13 Inline Fan.
const int PcFans = 12; //Names Arduino pin# 13 Inline Fan.
const int HeatingElement = 11; //Names Arduino pin# 13 Inline Fan.

//-------------------------//
//----------SETUP----------//
//-------------------------//
void setup()
{
  Serial.begin(9600);
  dht.begin();
  setTime(8, 29, 58, 1, 1, 11); //Used by the alarm system. Sets the time to Saturday 8:29:00am Jan 1 2011
  pinMode(13, OUTPUT); //Sets Arduino pin# 13 as an output.
  pinMode(12, OUTPUT); //Sets Arduino pin# 12 as an output.
  pinMode(11, OUTPUT); //Sets Arduino pin# 11 as an output.
  digitalWrite(13, LOW);
  digitalWrite(12, LOW);
  digitalWrite(11, LOW);
}



//------------------------//
//----------LOOP----------//
//------------------------//
void loop()
{
  digitalClockDisplay(); //Used by the alarm system. Displays the clock printout in the serial monitor.
  TemperatureControl(); //Calls the TemperatureControl function.
}

//----------FUNCTIONS----------//
void TemperatureControl()
{
  hum = dht.readHumidity(); //Read data and store it to variable hum
  temp = dht.readTemperature(true); //Read data and store it to variable temp
  Serial.print("Humidity: ");
  Serial.print(hum);
  Serial.print("%, Temperature: ");
  Serial.print(temp);
  Serial.println("(F)");
  delay(1000); //Delay 1 sec.
  HighTemperature(); //Calls the HighTemperature function.
  LowTemperature(); //Calls the LowTemperature function.
  HighHumidity(); //Calls the HighHumidity function.
}

void HighTemperature()
{
  if (temp >= 85) //If the temperature in the growing chamber rises above 85(F):
  {
    Serial.write(1);
    digitalWrite(InlineFan, HIGH); //Turn ON the relay for the Inline Fan.
    digitalWrite(PcFans, HIGH); //Turn ON the relay for the PC fans.
    TempTooHighTextMessage();
  }
  else if (temp <= 77) //Once the temperature in the growing chamber drops to 77(F) or below:
  {
    Serial.write(2);
    digitalWrite(InlineFan, LOW); //Turns OFF the relay for the Inline Fan.
    digitalWrite(PcFans, LOW); //Turns OFF the relay for the PC fans.
    TempTooHighClearedTextMessage();
  }
}

void LowTemperature()
{
  if (temp <= 70) //If the tempature in the growing chamber drops below 70(F):
  {
    Serial.write(3);
    digitalWrite(HeatingElement, HIGH); //Turn ON the relay for the Heating Element.
    TempTooLowTextMessage();
  }
  else if (temp >= 76) //Once the growing chamber temperature rises back up to 76(F) or greater:
  {
    Serial.write(4);
    digitalWrite(HeatingElement, LOW); //Turn OFF the relay for the Heating Element.
    TempTooLowClearedTextMessage();
  }
}

void HighHumidity()
{
  if (hum >= 75) //If the humidity in the growing chamber rises above 70%:
  {
    Serial.write(5);
    digitalWrite(InlineFan, HIGH); //Turn ON the relay for the Inline Fan.
    digitalWrite(PcFans, HIGH);  //Turn ON the relay for the PC fans.
    HumidTooHighTextMessage();
  }
  else if (hum <= 65) //Once the humidity in the growing chamber drops to 65% or below:
  {
    Serial.write(6);
    digitalWrite(InlineFan, LOW); //Turns OFF the relay for the Inline Fan.
    digitalWrite(PcFans, LOW); //Turns OFF the relay for the PC fans.
    HumidTooHighClearedTextMessage();
  }
}

void digitalClockDisplay()
{
  //Digital clock display of the time.
  Serial.print(hour());
  printDigits(minute());
  printDigits(second());
  Serial.println();
}

void printDigits(int digits)
{
  Serial.print(":");
  if (digits < 10)
    Serial.print('0');
  Serial.print(digits);
}