If you are used to Neville’s teachings you have come across revisions many times.- If you are new to him, here is a little explanation:
Revisions are mostly here related to imaginal scenes. What does that mean? You have for example a negative memory of breaking your leg, when you do the revision you change it to not breaking your leg. Which means you changed that memory – as it happened – with the difference that you landed perfectly on your leg and didn’t break it.
When are revisions useful?
– every time something negative happens (you think negatively, someone says something negative, etc)
– when you remember negative memories from the past
– at the end of a day
– when you have negative feelings
As you can see revisions can be used all the time.
What is mostly known is the daily revision at the end of a day.- Where you revise your day backwards and change everything negative into a positive scene.
I personally use revisions to change daily negative moments, feelings and talks in experiences during the day- while they happen or afterwards.
What I came to notice is that those revisions turn into manifestations quickly. 
This is the reason why I also use it as a manifestation tool. Whatever I want to manifest, I revise the related scene – if there is no related scene I just add it to a revised scene as an extra. 
You will be surprised how easy that is- plus it gives little to no room for doubt or fear. I mean, as soon as I revise that scene I go on doing other things- which takes away the time to think about that scene or worry. It’s done! – You are done with it.
I don’t really revise the past, because I don’t see much sense in doing so. I revise emotions and feelings that come up now and might be related to an event in the past. It’s also very effective in releasing past memories. The only reason for them to still effect us are the emotions and feelingsy which came from those experiences. One might prefer to go through every memory with revision – which is OK if you want to do so. But it is not necessary.
At the end of the day what I would really encourage everyone to do is playing with revisions. Try different styles of revisions and use it whenever you feel like it. Have fun with it!
ALWAYS keep in mind that you are God! The reason something might not work is because you have set rules and limitations to it – regardless of what someone tells you. It’s always ONLY you who MAKES or BREAKS desires, wishes or intentions, no one else!
Have a wonderful Tuesday!- For no reason it has to be a WONDERFUL DAY for manifesting! 
PS: As usual, feel free to ask for help or advice. We are all in this together. 