popo by himself still has dthrow chain grabs and combos. do lots of wding to fast c-sticking, like wd to down smash. his stuff can come out of nowhere. he should play a lot more evasively than when you have the two together. popo's wd and smashes are still awesome, so don't be discouraged when nana dies lol. especially against better players, who will be *****es and go after nana.
playing popo is all about fast wd's and mindgames. people have found it just as hard to fight against my popo as fighting against both of them together. a good trick is dash dancing, facing away from your opponent, wding backwards, and c-sticking towards them... mixup stuff like that. popo's mindgames are awesome because he moves so fast (normally when i do crazy dash dancing and wding together with nana, the dash dance desynch separates me from her. when you have popo alone, you can do all you like!)