Go round telling the people that you meet that your a time traveller. Tell them to back a horse called (make this up out of your imagination - not a real horse that you know the name of).
Then when you awake remember the name of the horse and write it down. If and when the grand national comes around next year and you see the name of that horse back it.
Also in your sleep go round telling the people that you meet your a time traveller and that you found them by watching old youtube videos.