My recomendations. 

So for the hotel breakfast buffet I eat a lot of watermelon, banana, pineapple (take a banana with you so you have a snack later on the day) and egg. If they have bacon ask if it's been fried in olive oil and ask if it's possible to know if it's been added sugar to it.

If they have salad to sandwiches I eat that with a slice of tomato just like it is.

Remember to ask if the juice is 100% fruit juice. If it is - go ahead and drink. 

Don't forget to not sweeten your coffe or to have milk in it, I know it's hard but you can make it.

On the airplane what to eat and drink on paleo:

The juice if it's a 100%

You should be drinking to glases of water every 30 minutes, otherwise you will feel a bit hungover the day after.

To the airplane food the often have sauces, skip it. I'm sure they have sugar in it, scrape it of if it has been added already.

If it's possible write to the airline and say that you have allergies in a head of time, that way you will get food that is no problem. 

They sell cashew nuts, go nuts on those.

Cashew nuts have magnesium in it so eat it only when you wanna stay up once magnesium gives energy. For example if you are travelling to a far away contry with time difference eat it to stay awake so that you will instead sleep on location were it is night.

More tips like these in the future when I'm a more experienced cabin crew.