She generally gave herself very good advice, (though she very seldom followed it), and - Lewis Carroll

I daresay you haven't had much practice. When I was your age I always did it for half an hour a day. Why, sometimes, I've believed as many as six impossible things before breakfast.

"It'll be no use their putting their heads down and saying "Come up again, dear!"
I shall only look up and say "Who am I then? Tell me that first, and then,
if I like being that person, I'll come up: if not, I'll stay down here
till I'm somebody else" — but, oh dear!' cried Alice, with a sudden burst
of tears, 'I do wish they WOULD put their heads down! I am so VERY tired
of being all alone here!"

I'm sure I'm not Ada for her hair goes in such long ringlets, and mine does'nt go in ringlets at all; and I'm sure I'm not Mabel, for I know all sorts of things, and she's she and I'm I, and-oh dear, how puzzling it all is! i'll try if I know all the things I used to know. Let me see: four times five is tweleve, and four times six is thirteen, and four times seven is-oh dear! I shall never get to tewnty at that rate! However, the Multiplication- Table doesn't signify: let's try geography. London is the capital of Paris, and Paris is the capital of Rome, and Rome-no, that's all wrong, I'm certain! I must have been changed for Mabel!