Cribbage - Strategy

1st time poster in this forum section (normally my habitat is Omaha 8 and Stud 8).

Seemed like a good place to post this. I've known how to play for about a year and a half and I think I do OK at it. I can count properly, rarely miss points, but want to take my game to the next level. Like a pub poker player who wants to be competent in casinos.

What tips have you got with regards to hand selection and pegging that will help me improve?

Right now for example in pegging I believe it is best to open pegging by leading with a small card so my opponent cannot make 15 immediately, the best card being a 4. Am I correct? If you had a choice between leading any card, which one would you pick, and if you could choose between A, 2, 3 or 4, which one?

In what situations does it benefit me to try to encourage my opponent to make runs in pegging? It seems to me to vary in benefit according to how many points have been scored so far and also what cards one holds.

How do you put your opponent on a hand?