DS2 is almost 5 months (textbook/touchy) and has finally started taking longer naps on his own, horray! He's been a catnapper practically since birth and it didn't take me long to figure out that longer naps were going to be developmental for him (DS1 was the same).
I may be a little different in that I didn't do much to try and change it. I just tried not to stress about it and figured he'll get there when he gets there. I would offer his paci or AP him to try and get him back to sleep, sometimes it would work, sometimes it wouldn't (and when it didn't, oh well!). Around 3.5 months we started extending them easily with the paci, I realized it may become a prop and in fact it did seem like it may be, but again, oh well! It got him back to sleep! Now a week shy of 5 months, as long as he's not OT, he's taking 1.5 hours naps all on his own!
I'm going to be honest and say I'm SO happy that I didn't spend hours upon hours of ssh/pat, HTTJ, etc. With a two year old to take care of as well, I think it would have only stressed me out.
So for those of you with catnappers, my advice would be to try not stress about it, just enjoy them while they're little. For most of you I'm sure longer naps WILL happen eventually!
Edited: I changed the title of my post because *I* didn't really do anything, DS did it all on his own!