You need to use neutron pack + neutron gun to attract the ghost.

Equip neutron pack + neutron gun + googles (you can buy it at BUYNEUTRON)

Attract ghost nearby you

Place ghost jars on the bottom platform

Attract the ghost to be on top of the placed ghost jars

Sorry if you couldn't understand me, you can watch youtube videos about "How to catch ghost in Growtopia". It might helps you.

Cuz they know theres rickroll in the jar

shoot the ghost ass until it hit u and put the jar below you and keep shooting at the ghost ass... work all the time

Put the jar below you, once the ghost is on you. Recommend using like plats and not trying to jump and pull