Is there anything I need to do before imprinting water to make it more effective?

You could try vortexing water. I believe it should precede imprinting.

So it's more about making water structured than imprinting, but one shouldn't plant roses when forests are on fire :). When you have water structured, then imprinting it is far easier and long lasting, I believe.

There's a simple way of making water structured via applying a Spooky2-XM generator, and a one-dollar electric motor (and a vortex).
I made a film showing the procedure - it's in Polish, but self-explaining, all the more I added an explanation in English under the film. You may want to see it:

The water I get after 15 min of vortexing is something much more than I expected. Water is absolutely tasty. If you want to know what "absolutely tasty water" means follow this procedure and drink the water.
Additionally, only with such water further steps (imprinting) "get wings", I believe.

For more details, please check the link from:
https://www.spooky2.com/forums/viewtopic.php?f=6&t=10409