Is there any restriction about using Lay on Hands twice in a round (swift action to heal oneself and standard action to heal an ally)?
Also:
PRD on Channel Energy "A cleric must be able to present her holy symbol to use this ability". Does it mean that he needs a free hand to channel?
Edited: PRD instead SRD
Is there any restriction about using Lay on Hands twice in a round (swift action to heal oneself and standard action to heal an ally)?
I don't think there is a restriction on that. Perhaps not even on using it on himself twice, but that's a tougher call.
Also:
SRD on Channel Energy "A cleric must be able to present her holy symbol to use this ability". Does it mean that he needs a free hand to channel?
SRD or PRD?
I usually regard that as a "must be able to touch it", but a free hand would be a valid interpretation as well.
I would actually say you don't need to have a free hand to use channel energy. A holy symbol hanging from your neck under a cloak could be "presented" by opening the cloak. Also the holy symbol could be affixed to a shield or other item, and depending on the diety could even be a weapon itself. An equally valid interpretation could be as long as the holy symbol is readily available (has one on their person/not packed away)/isn't hidden (stealth mission/disguised/etc.) it would be possible to channel energy. I don't see having certain clerics being able to do something like this more easily than others because of deity choice being a "fair" ruling.