Demo implementation of IComparable<T>

Program.cs

class Program
{
    private static WorkDay workday1 = new WorkDay { Day = 1, DayName = "Monday" };
    private static WorkDay workday2 = new WorkDay { Day = 2, DayName = "Tuesday" };
    private static WorkDay workday3 = new WorkDay { Day = 3, DayName = "Wednesday" };
    private static WorkDay workday4 = new WorkDay { Day = 4, DayName = "Thursday" };
    private static WorkDay workday5 = new WorkDay { Day = 5, DayName = "Friday" };
    private static Shift shift1 = new Shift { Start = TimeSpan.Parse("08:00"), End = TimeSpan.Parse("12:00"), Name = "Shift 1" };
    private static Shift shift2 = new Shift { Start = TimeSpan.Parse("12:00"), End = TimeSpan.Parse("16:00"), Name = "Shift 2" };
    private static Shift shift3 = new Shift { Start = TimeSpan.Parse("16:00"), End = TimeSpan.Parse("20:00"), Name = "Shift 3" };

    static void Main(string[] args)
    {
        Console.WriteLine("Hello World!");

        List<Schedule> list = new List<Schedule>
        {
            new Schedule
            {
                Shift = shift1,
                WorkDay= workday1
            },
            new Schedule
            {
                Shift = shift2,
                WorkDay= workday4
            },
            new Schedule
            {
                Shift = shift1,
                WorkDay= workday2
            },
            new Schedule
            {
                Shift = shift2,
                WorkDay= workday1
            },
            new Schedule
            {
                Shift = shift1,
                WorkDay= workday5
            },
            new Schedule
            {
                Shift = shift2,
                WorkDay= workday3
            },

        };
        Console.WriteLine("Before Sorting");
        foreach (var item in list)
        {
            Console.WriteLine($"{item.WorkDay.DayName} - on {item.Shift.Name} from {item.Shift.Start} to {item.Shift.End}.");
        }
        Console.WriteLine("\n\n\n\n");

        list.Sort();
        Console.WriteLine("After Sorting");
        foreach (var item in list)
        {
            Console.WriteLine($"{item.WorkDay.DayName} - on {item.Shift.Name} from {item.Shift.Start} to {item.Shift.End}.");
        }

        Console.ReadKey();
    }
}

Schedule.cs

class Schedule : IComparable<Schedule>
{
    public int CompareTo(Schedule other)
    {
        int result = 0;
        result += WorkDay.CompareTo(other.WorkDay);
        result += Shift.CompareTo(other.Shift);
        return result;
    }

    public WorkDay WorkDay { get; set; }
    public Shift Shift { get; set; }
}

Shift.cs

public struct Shift : IComparable<Shift>
{
    public string Name { get; set; }
    public TimeSpan Start { get; set; }
    public TimeSpan End { get; set; }

    public int CompareTo(Shift other)
    {
        if (Start > other.Start)
            return 1;
        else if(Start< other.Start)
            return -1;
        return 0;
    }
}

WorkDay.cs

public struct WorkDay : IComparable<WorkDay>
{
    public int Day { get; set; }
    public string DayName { get; set; }

 
    public int CompareTo(WorkDay other)
    {
        if (Day > other.Day)
            return 2;
        else if(Day<other.Day)
            return -2;
        return 0;
    }
}