If you ever read the third book in the Oversoul Seven trilogy, you's see a story really built around this idea.
Sometimes I get up in the morning purposefully looking for clues as to whether I'm on a different "world line" than when I went to bed. As Seth points out, you can't tell because these jumps are literally invisible physically. My only clues are how people behave differently from moment to moment.
When you remember that our universe blinks in and out of physicality so that, to us, it looks like we sense things about 50 times a second (that's what the brain is tuned to) then it's no surprise that we can "blink" back to a slightly different reality. Since we hold such a strong belief in continuity of space and continuity of linear time, then there is usually no major change from blink to blink.
What is even more interesting, each new moment comes with a completely consistent set of past "memories" and future probabilities ... so memory doesn't work to spot the change.
What a neat reality we live in! Enjoy!
"It seems also that the future must be built upon that one known species or world past. Often it may simply sound like a figure of speech when I talk about probabilities. In many ways it may indeed appear to be almost outrageous to consider the possibility that "there is more than one earth", or that there are many earths, each similar enough to be recognizable, yet each different in the most vital respects.
"This particular house exists. Yet you may open the door on any given day to a probable world from your immediate standpoint, and never know the difference. This happens all the time, and I mean all the time.
"You move through probabilities without knowing it. The transitions are literally invisible to you, though they may appear as trace elements in your dreams. As a diamond has many facets, so does your reality in that regard."
(The Nature of the Psyche, Session 797)