Dizziness will happen at first, I would be lying if I said other wise. This is the number one reason most people will give up after one flight. BUT! and its a big but, the most common thing you will hear from experienced pilots is, "You get used to it." This is true. Hovever depending on your age, that time to, "get used to it" will vary.
Such pearls of wisdom are not much help when you have sunk to your knees or keeled over feeling like the the world is going in strange multiple directions simultaneously whilst clutching the ground and wishing it would all go away (Similar to a past expedience I had with a very nice cake that a few too many herbs in it. Far out, did not do it justice).
Flying a small team race model for the first time recently after many years; after running the tank out, at least I didn't disgrace myself before I it stopped and landed, I had my legs NOT go in the direction I was pointing, ending ignominiously on my back with with all the old familiar feelings. Bear in mind I do fly fairly regularly, so this was stark reminder that I need to heed my own advice and follow my own methods before trying anything different.
With a little preparation and practice without ever touching a model, the worst effects can be mitigated. This also works if you have a long layoff from flying; 30 years was my longest period. As an aside, this was how I learned and practised the stunt schedule from start to finish including all the had signals, it becomes ingrained after a while and no thought, or not so much, is needed when concentrating on the manoeuvres. The same will be true for carrier. Forgetting to signal the the slow run or landing attempt, can be disconcerting at best, and resulting in losing a flight score at worst.
My method:
Because it works for me so it's worth a shot.
Stand in the middle of a room with enough space to turn around with your preferred arm out stretched, left or right, and avoiding knocking things over. It's best to do this when no one is around or those close to you might think it's time to call for those nice young men in their clean white coats (not too subtle song reference there).
Now turn around slowly as many time as you can manage, and stopping when you begin to feel out of sorts. Remember! Any dizziness will increase when you stop turning. So stop any time if you feel slightly unsteady, not actually dizzy! or you will end up wanting to vomit. Take note of how many rotations you managed.
You only have to do this once a day for about a week, increasing your rotation number of laps a little bit each time, Don't try to rush things. It helps if you look at you outstretched hand, this is good for simulating the the effect of looking at the model when flying and not mentally letting the background distract you. The furniture whizzing by can be unnerving at first.
Each day try to increase the number of laps by one each time, the goal is around 7. This not a hard and fast rule, just doing a handful of turns a day will slowly build up your resistance. Doing this occasionally in spare moments all helps. If you feel up to it also increase your rotating speed gradually over time.
The following is only necessary if you are aiming to compete on competitions.
Carrier competition fast run can be around 50 to 60 mph, and up into the 90's for those that know what they are doing.
But lets assume with a beginners model with decent wing area on average +/-35 seconds to do 7 laps on 60 foot lines. this gives a rotation of 5 seconds per lap.
When swivelling around in your living room, this is the the target you are trying to work up to. If you can manage 7 turns in 30 in secs, you are ready. It will take time to get there, don't rush it.
Of course the first time you fly I will be surprised if you feel no dizziness at all. If you have prepared for it, this should pass fairly quickly. If you manage to walk away from your first flight in drunken wobbly strait line, without falling over! Consider it a success and take a breather. If you do fall over at the end but the model is still in one piece, congratulations are still in order. Most likely you will get a flood of emotions from delight (Yay! I did it!) to all the boundless possibilities that open up. The worst thing to do is think you will never get over this dizzy feeling; YOU WILL, and much faster than you think at the time
Each successive flight will improve until you forget about and dizziness. This change seems to do some sort of subconscious rewriting of our brains. Once acclimatised, it seems to last, only fading over long periods of no use. Even then it seems easier to get over even if there is a long layoff.
Once you get over the early flights and feel more confident, in your living room try flying the whole flight form start to finish with all the added hand signals including the launch signal if someone is holding the model for you.
Launch signals are more important than you might think. Arbitrarily waving you free arm about differently each time can be confusing for the launcher. Because people roped in to launch can be anyone standing around nearby: make sure they know what your signal will look like, and also when not to let go if something is not right. One useful phrase is, "If in doubt DON'T!"
Having someone let go just as you move a hand to a ready position before you drop or sweep it, will catch you off guard. If you are unlucky, that may have unintended dangerous consequences..
Also be Aware!
If you suddenly find yourself for what ever reason flying very high at speed or with a much faster model, the dizziness will return, sometimes with vengeance! Same rules apply. Take the time to acclimatise and get used to it.
There is one advantage these days that did not exist in the early days, and that is throttle control. Achieved by various means covered elsewhere, this alone can ease anyone into control line flying. Being able to regulate or stop the engine/motor when needed is a game changer when learning.
I hope this can help someone get over this, not inconsequential initial hump, and start enjoying control line flying. It is all well worth the effort in the long run. And if this hasn't deterred you completely, read the other pages.