Add list-s command to UG

docs/UserGuide.md

@@ -171,28 +171,50 @@ Adds a schedule to a specified tutor.
 * `Wrong input: s/`: The start time entered is not in datetime format.
 * `Wrong input: e/`: The end time entered is not in datetime format..
 
+### List all schedules: `list-s`
+
+Displays a list of all schedules in the address book in a table format.
+
+
+![view schedule](images/viewSchedule.png)
+
+**Format:** `list-s`
+
+**Example:**
+* `list-s` shows all recorded schedules in the address book.
+
+**Expected output:**
+* Displays a table of schedules with columns for List number, Tutor Name, Start Time, and End Time
+* If there are no schedules in the address book, displays a message telling the user to add a tutor with `add-s`.
+
+![empty schedule list](images/emptyScheduleList.png)
+
+**Error messages:**
+* `Too many parameters`: `list-s` does accept any parameters other than its own command. (E.g. `list-s 1` will result in an error).
+
+
 ### Deleting a schedule: `delete-s`
 
 Deletes a schedule in the address book based on their index number in the table of schedules listed.
 
 ![delete schedule](images/deleteSchedule.png)
 
-Format: `delete-s INDEX_NO`
+**Format:** `delete-s SCHEDULE_INDEX`
 
-Example:
+**Example:**
 * `delele-s 5` deletes the schedule that is indexed as 5 in the schedule list.
 * `list` followed by `delete-s 2` deletes the 2nd schedule in the schedule list.
 
-Acceptable values for each parameter:
-* `INDEX_NO`: NUMBER Only numerical input that ranges from 1 to the last schedule shown in the list of schedules
+**Acceptable values for each parameter:**
+* `SCHEDULE_INDEX`: NUMBER Only numerical input that ranges from 1 to the last schedule shown in the list of schedules
 
-Expected output:
+**Expected output:**
 * `Schedule has been deleted: Tutor: John Doe; Start date: Sep 15, 2023 09:00; End date: Sep 15, 2023 11:00;`
 
-Error messages:
+**Error messages:**
 * `Index number given is out of range`: Given index is out of range.
-* `Invalid value in parameter INDEX_NO`: Parameter given is not a numerical value.
-* `Missing parameter INDEX_NO`: A numerical value is not provided when calling the command `delete-s`.
+* `Invalid value in parameter SCHEDULE_INDEX`: Parameter given is not a numerical value.
+* `Missing parameter SCHEDULE_INDEX`: A numerical value is not provided when calling the command `delete-s`.
 
 
 _More details coming soon ..._