Knowing the light is there for them and will reach out to them, having a corresponding thought about this begins to set the stage, for it will raise the person’s vibration through having something positive to anticipate. And it creates the possibility of having a resonance with the divine realm, which will be reaching out itself from the light and it is much akin energetically, to calling someone by name and increasing the chance they will hear the caller and move towards the sound. So any way the person can think or envision being in or summoning light to them will be heard and answered, and then it is a function of strength and the power of intention as to whether things can take hold and proceed from there to a full transition. But that would be a good start and is good to have in the thoughts as imagery.
The best and most powerful thing would be a direct appeal to Creator and to have that in the expectation, to know that Creator can always hear one’s thoughts and will answer requests is the most powerful tool available to any human. The fact that so many prayers seem to go unanswered is not evidence to the contrary about the power of appealing to Creator at the time one passes to have a deliverance to the heavenly realms.