What is the best strategy to evolve Eevee to Umbreon in Sapphire?

Question

Reposting this question for archival purposes.

"I’ve recently become the League Champion in Pokémon LeafGreen, and I’m using my copy of Sapphire to obtain all of the Gen 3 Eeveelutions. Unfortunately, I haven’t been able to wind any good guides or strategies for evolving an Umbreon. I understand the basics, I’m just looking for a more detailed plan."

Answer 1

The fastest way to raise an Eevee's friendship/happiness in Sapphire and Leafgreen is first making sure it's holding a soothe bell, and then leveling it up (+7 if current friendship is below 100, +4 if it's between 100 and 199, +3 if it's above 199), feeding it vitamins (costs 9,800 money, same boost as leveling it up), or having Daisy in Pallet Town groom it (can be done once every 500 steps, +4 regardless of current friendship). A Pokemon can evolve if it has at least 220 friendship, and you can check its friendship by talking to Daisy or the friendship rater in Verdanturf Town. Eevee can evolve into Umbreon between 12 am (midnight) and 12 pm (noon), and you can check the time in Littleroot Town.
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