[lalchi]

I like to make my alias in two part and describe the character in few words

One variable part + One static part

For me, a good alias is something you can change it and still make the character stick to it only by changing the variable part

For example Lalchi's alias is "Curious tail"

Cause he's curious and he has a tail because he's a redtail

But when he is in his christmas outfit he's the "Joyfull Tail" or on his halloween costum he's the "Maniac tail"

This applied to each one of my characters. If I ever have to change their design for occasions.

[Moku203]

I personally just kinda throw one together that sounds good phonetically and looks good visually that can explain the general air or look of said character. 

Kiki being a good example, she has alias' like Mystical Magician for her magician outfit, Glittering Glamrock for her rocker outfit, Raging Recondite for her anger red star look, and of course Wandering Wonderment, and Monochrome Meanderer for her Clown and Mime respectively.

otherwise it's often very basic things such as Aynn being Motherly Zeran, Armored Zeran, Suited Zeren etc etc.

[Dezark]

I typically just match a character alias to their theme or occupation if I can normally; so Artificer Feline or Voiceless Blacksmith for most, some have more random or unique alias to match their backstory or intention behind it, like my apertauri being "The Forgotten One" since she from some old tribe I threw together a massive lore for.. or the Emerald Eyed Daemon since they're the daughter of someone who claims to be a demon, etc.

Typically long as it feels fun enough for it and rolls well enough off for it I like it.