MyJob job = new MyJob (JobName, webApp);
// Set my custom property!
job.Properties.Add("test", "test value");
SPHourlySchedule schedule = new SPHourlySchedule();
schedule.BeginMinute = 0;
schedule.EndMinute = 59;
job.Schedule = schedule;
job.Update();

public override void Execute(Guid targetInstanceId)
{
    try
    {
        // read my coustom property
        var test = this.Properties["test"].ToString();