Congratulations Shafs!
I have introduced 100s of people to aerobatics over the last 40 years, both as passengers and students.
The trick is to follow the above guidance of fresh air inflight and food intake pre flight, then do short flights, gradually increasing duration. The old story of wishing you were up there, rather than wishing you were on the ground.
You may also want to try Sea Bands, you can pick them
up from pharmacies, they use pressure pints to reduce motion sickness. I was very sceptical about their effectiveness, but have had many people use them with great success.
Maintaining situational awareness reduces the tendency to become ill, have the pilot tell you where they are looking during manoeuvres, or if unsure, have a quick look to see where they’re looking. The objective is to maintain sight of the horizon.
enjoy!