I have a few processes, but I'll explain how I named 3 of my stories "Little Dreamer Boy", "A Flower Just For You" and "The Nameless Relic". All 3 are under the SUMMON! umbrella, which is named after the ever present power that permeates all 3 series.
"Little Dreamer Boy" was named for the main character. A Little Boy who's tied to Dreams. The title describes the main character. Think "Chainsaw Man" (Man with a Chainsaw for a head), "Bio-Booster Armour Guyver" (The Guyver is a Bio-Booster Armour), "Meitantei Conan (Conan is a Detective).
"A Flower Just For You" -or- "A Flower For You in Full Bloom" is the overall goal our main character has. She wants to give flowers to everyone she meets out of gratitude. I want to give you this. A simple phrase than encapsulates the story. Think "Love is Hard for an Otaku" (well, it is), "Even If It Was Just Once, I Regret It" (already, the speaker's perspective is clear, a regrettable action.)
"The Nameless Relic" (title) refers to "The Nameless Relic" (object), the central item in the story that everything revolves around. Think "Dragonball" (Collect all 7 and make a wish) and Cardfight!! Vanguard (The Game the characters play is Vanguard and to play it is called a Fight or Cardfight).
I'd say think about what the most important part of your story is. Is it focused on one character? Is there a central phrase you want to emphasize. Is their an object, sport or game that is at the forefront? Most importantly, does this title sound at all like another series. If so, try and rewrite it to avoid confusion, or phrase it slightly differently. Even more importantly, are you happy calling your series that. Can you say the title with pride? If yes, then that's the title for you.