A couple of quick thoughts:

1. If you don't HAVE a child (and this includes those who have "practically raised" a brother/sister/cousin/nephew/niece/etc) you honestly can't give much advice. why? see number two.

2. there is no guidebook, nor a particular pattern to follow (referencing what may have worked for someone else, what "professionals" say, and what you thought you would/wouldn't do prior to being in the parental/guardian position). anyone who has been or is there will/should give the following advice: do the best you can with what you have.

finally, it's a whole lot easier to say "i love you" than to show it consistently.

(as i close i realize i probably didn't address the specific questions put forth, but nonetheless this is what came out)