Hi Sally,
Welcome to the forums

I used to be scared of flying (though never let it stop me!) until I read "Flying without Fear" by Captain Keith Godfrey. It's fab, and at first I'd take it on flights with me and have it in the seat pocket - now it has a home on my bookshelf gathering dust!
He goes through every single fear, and yeah, you can skip over many, but then you find your own.
The best tip I got regarding bumpy flights (aka turbulence) from the book was this: tighten your seat belt as tightly (but as comfortably) as you can. Put your head back in the seat, shut your eyes, and let your head rock to the movements of the plane, but pretend you're on a bus! Sounds crazy, but it worked for me!
Hope the flight goes well and that this tip helps if it is rocky

Also remember that the pilots and the planes are put through rigorous training to deal with anything, and will never deliberately fly into a storm. It's not the best when the pilots don't warn you or explain what's going on up there if turbulence is experienced, but if you think about it like driving across a bridge in high winds in your own car, you don't automatically say to the passengers about how windy it is while you're controlling it - to pilots, it's that same second nature when they're in their 'vehicles'