I cast a chart for when I would talk to my friend and was wondering which significator I would use? The third for communication? But that could be writing or calling correct? The eleventh for friend? Also, if the two signifcators were in aspect but one had to switch signs before perfection does that mean it will not come to pass despite the question being when not will? Thanks for the help!

The 11th signifies friends. 3rd would show the nature of communications. Ruler of 11 contacting 3 or ruler of 3 could also bring communication from the friend. I have seen Moon perfect out of sign but be aware that a major change, shown by the new sign will be necessary to perfect. Also, anything that happens between the two significators making contact will prohibit and interfere, if it is any planet not one of your significators or of the question, unless it is a collection of light where a 3rd party brings you to perfection.

Thanks Aquarian! I'm finding it easier to see what's going on with a chart after the fact. But this really helps.