Line Following contest

The following rules are based on the line following rules from the Robogames website:

The objective of this contest is to complete the course in the shortest period of time while accurately tracking the course line from start to finish.

1. Size and Weight Limits: these do not apply at RSSC contents. If your robot can fit on the course, it can compete.

2. Course Time: time is measured from the time the robot crosses the starting line until the time it crosses the finish line. A robot is deemed to have crossed the line when the forward most wheel, track, or leg of the robot contacts or crosses over the line.

3. Time Limit: a maximum of 3 minutes is allowed for a robot to complete the course. A robot that cannot complete the course in the allotted time shall be disqualified.

4. Timekeeping: time shall be measured by an electronic gate system or by a judge with a stopwatch, based on the availability of equipment. In either case the recorded time shall be final.

5. Autonomous Control: once a robot has crossed the starting line it must remain fully autonomous, or it will be disqualified.

6. Arena Edges: a robot that wanders off of the arena surface will be disqualified. A robot shall be deemed to have left the arena when any wheel, leg, or track has moved completely off the arena surface.

7. Losing the Line: any robot that loses the line course must reacquire the line at the point where it was lost, or at any earlier (e.g. already traversed) point.

8. Second Attempt: any robot that loses the line course and fails to reacquire it will be allowed a single reattempt. The robot must start the course again from the beginning, and if it loses the line course on its second attempt it will be disqualified. 

9. Power of Officials: the decisions of all officials regarding these rules and the conduct of the event shall be final.

10. Course Specifications: The line following course can be either drawn using white tiles, white paper or directly on the floor with black electrical tape, depending on the availability of contest material. The floor tiles are grey. This might pose as an extra challenge compared to a course with a white underground. Be prepared for your robot to compete on a less-than white background.
There shall be a starting area at the beginning of the course and an exit area at the end. The line course starts inside the starting area and ends inside the exit area. 
The start and end points of the line course shall be clearly marked via a transverse line no more than 2mm wide. There shall be a 10cm gap in the starting and finishing lines where the line course passes through them. 
Characteristics of the line course:

• There shall be no crossovers (e.g. places where the line crosses itself)
• Switchbacks and hairpins are possible, but the adjacent sections of the line shall be no closer together than 15cm when measured from the center of each line.
• The line course shall have 1 or more sharp right-angle, but no angle will be greater than 90°.
• The closest approach of the line course to the edges of the arena shall be no less than 15cm, measured from the center of the line.

Here is link describing how to make line following course.