If you're a new player, my advice is don't multiclass in order to pick up swift/immediate action options. You're better off sticking pure Cleric until you can take a Prestige class (such as Radiant Servant or Church Inquisitor) that gives real class features and also advances Cleric spellcasting. You can use your spell slots for swift/immediate actions.
Close Wounds, for instance, is an Immediate Action spell from the Spell Compendium that heals 1d4+CL hit points to a target in close range - it can literally save lives by preventing damage that would otherwise kill someone. It's a 2nd level spell, so you could cast it right now if you wanted.
Blade of Blood is a 1st level swift action buff from PHB2. Lets you touch a weapon and have it deal +1d6 damage (or +3d6 if you voluntarily take 5 damage). It's Target: Weapon Touched so you could use it on an ally's weapon if you wanted to.
But even better than using swift action spells is using spells that have no action cost at all, because you pre-cast them out of combat - look for buffs with minute/level, 10 minute/level, or hour/level durations, and cast them when you suspect a fight is coming. Shield Other, Bless, and Shield of Faith are good spells from the PHB.
If you really know what you're doing, you could go for an alternative Ruby Knight Vindicator build using a Swordsage base. When you hit your 4th Cleric level, use the Retraining rules from PHB 2 to retrain your 3rd character level into Swordsage, and retrain whatever feat you took at 3rd level to Martial Study (one of the 1st level Devoted Spirit maneuvers). You have to retrain both the class and the feat so that your maneuver gets a recovery method, but the end result is at 4th level you're a Cleric 3/Swordsage 1. Use your Swordsage level to pick whatever boosts/counters seem useful.
Later, aim to get in to the Ruby Knight Vindicator prestige class (this is why you needed the Martial Study feat), advancing your Swordsage maneuvers and your Cleric spellcasting.
