The key is to, as soon as the new scene begins, make it clear that it is a continuation of the previous scene. Show the audience something they're familiar with, such as a scenario or camera angle used previously. The longer the audience goes without noticing you are resuming a previous scene, the angrier and more confused they'll be when they finally understand what's going on.
If the gap is very long, you may replay a little bit of what was last seen. Christopher Nolan's Memento did this and it was brilliant. It works even better if what is shown is a very unique and quick event (such as a something breaking or someone being shot).
You can also insert in the scene a clock, a calendar or have a character announce the day/time, but be careful to have believable grounds for this to happen (don't have Bruce stop his epic fight with Wayne just to take a look at his watch).
If all else fails, you can always insert a little text as the scene begins. Something such as
London 11:21 AM - 05/12/1907 These are especially common in spy or detective movies. Be very careful when using them, as they become annoying very quick.
The best thing you can do when trying to find out how to do something is to study where it has been done before. In this case, try watching movies with a lot of time jumping. I suggest Tarantino and Nolan as a good starting point.