Femme Fatale
Banned
Delcatty is, to be frank, a horrible Pokemon. If you still want to use it, any of these three sets are viable:
Delcatty @ Leftovers
Impish / Bold
Trait: Cute Charm
252 HP / 252 Def / 6 SpDef (or Speed)
~ Body Slam / Sing / Thunderbolt / Ice Beam
~ Substitute / Protect
~ Calm Mind / Wish
~ Baton Pass
Lol all these sets are copied and pasted from Smogon but how little the amount of thought that was put into those sets was baffling. On a Calm Mind or Charge Beam passer, do not use Attack EVs. Truth be told, you're not hurting much with 252 Atk either so that can be ditched. If you're using Calm Mind, you're better off pumping your Defence up. If you're going to focus solely on passing Substitutes, 252 Speed couldn't hurt but Defence will more than likely be the way to go. Speed EVs here are pretty much useless.
Delcatty @ Leftovers
Impish / Bold
Trait: Normalize
252 HP / 252 Def / 6 Atk (or SpAtk or SpDef)
~ Thunder Wave
~ Sing
~ Heal Bell / Wish
~ Return / Protect / Fake Out / Sucker Punch [/b]/ Icy Wind[/b]
Delcatty @ Salac Berry
Jolly
Trait: Cute Charm
12 HP / 244 Atk / 252 Spe
~ Assist
~ Substitute
~ Return / Body Slam
~ Payback / Faint Attack / Sucker Punch
No, that last one should not be used unless you're building an Assist team and in-game, that's foolishness.
I realise I criticised Smogon for "putting little thought into their EVs" and then used 252/252 spreads but you will need to pump up Delcatty's defensive stats (and Defence is better than its SpDef) so it can stay alive. Its support options are vastly better than its offensive options so focus on keeping it alive and taking the odd defensive hit with a Wish/Protect combo or paralysing Ground-types for fun.