Pitch Setup

A line marking fluid is applied to the grass leaf to set out the dimensions of the playing surface and ensure the match official can referee fairly. The fluid used is normally white but differing colours can be used where multiple pitches are marked on the same area.
The lines should be clearly visible from 60m away and be between 50 and 100mm in width of line.
The marking out should be undertaken when the grass is dry to ensure the marking fluid dries on to the grass properly and so it remains bright.
For pitch dimensions follow the link.

https://resources.thegma.org.uk/rugby-league/pitch-dimensions-0

There are several different types of line marker available with wheel to wheel and spray markers being the most common.
The wheel-to-wheel maker transfers the fluid from a tank to the pitch via a transfer wheel joining the front wheel that runs on the pitch. For the brightest line using this type of marker the line needs to be marked in two opposite directions. A string line should also be used to keep the lines straight. The string should be laid running alongside one side of the line to be marked. Pegged in at one end and from the opposite side pulled tight so the string butts up to the line to be marked and then pegged in place. It is easiest to carry out this operation with two people.
Spray markers use specialise fluids that are pressurised and dispersed through a nozzle on to the grass. The line normally only needs to be sprayed once as the spray marker sprays both sides of the leaf ensuring a good covering of fluid to leaf. Again, string should be used to assist with keeping the lines straight.
Straight lines not only look better but they ensure the referee can judge the game better.

Benefits
• Bright clear straight lines ensure that the game can be officiate fairly enhancing the enjoyment for the players and those watching the game
• Straight lines are aesthetically more pleasing and will give a better first impression of the pitch to spectators, officials, and players.
Practical Tips
• Lines should be clearly visible from 60m
• String line should be used to keep lines straight
• Marking out is best done after cutting and when grass leaf is dry