My boy is just over 2 years and still chucks a wobbly every now and again.  We have said to him if you can't do it then try and try again.  Teach him to ask for help if he needs it.    We say I know your fustrated but if you can't do it ask for help please...  He usually does..... 

Have patience, this is just a stage and a learning curve for him,

Yes this is a really normal stage. It gives me a little bit of a chuckle inside when I see kids at work doing this. Like they cant turn the pram around as there is something in the way. I just watch and try to give encouragement and ask them to keep trying. There are some with little patience that will end up throwing the pram and losing there temper. Sometimes you may need to step in and help. Best to get them to ask you as you want them to learn this such as, would you like some help. If you step in everytime though they cant get that feeling of accomplishment which we want them to have. Very normal and I just suggest balance but try to get him to ask you to help him in his way rather then just stepping in and doing it for him