Believe it or not, most of us do this FOR that "nervous" feeling of adrenaline. It's the same thing with gamblers. its a high. It's the reason most of us go broke (chasing big gains that make our hearts pump). It'll never go away. But I agree a smaller position size does make it easier.
start paper trading and you will see that you still nervous .... because size of the position has almost nothing to do with that what has a lot to do with that is confidence that you will do what has to be done when market will start his usual unexpected moves, in other words you do not have confidence in the method at hand or that you can use it the way it supposed to be used traders are nervous because they afraid of making mistakes and errors the mistake is a trade without any method or with the method that does not work, the error is not applying the method in which one believes correctly (because of luck of concentration, or unusual, neverseenbefore situation on the market, or trading beyond the limits of the method) my grandma also has confidence in the direction direction is nothing there is no right or wrong direction, what matters were you entered and where you exited the trade, and how you assessed the situation while you in the trade
Trade small, build on past success, if it's uncomfortable you are on the right track, it channels your subconscious which controls experience. If it's painful you are wrong, if it is easy or you want to trade it you are wrong. That is the weaker, greedy, conscious psychology coming through. Follow that and it will be a wild ride, some can make it work but your effort will outweigh your reward. Confidence is simply perfection from your experience, plan your trade and trade your plan. The trade should come to you, search for it and you will be wrong, slow and steady wins the day.
Whether I was paper trading, doing a one lot or 100 lot, equally nervous, since it was all equal, just pushed size up. Got automation, am numb to it all. Yea, I tried tiring myself out with exercise before, during, meditation, music, screaming, throwing keyboards, once a super ball----EMS showed up... You putting something you value on the line, human nature to feel uneasy or just plain ready to toss up breakfast, lunch, midnight snack...for me had nothing to do with confidence, think perhaps childhood has much to do with it-grew up very poor, so I value it much more. Often wonder those who grew up in more affluent families don't have the fears as much? Equally, how many of you are screaming at the screen when you are short and market is plummeting? That is a fun feeling, doing an Irish jig, talking to the cat, dogs howling and "come on you son of a b*tch drop", YAHOOOOOOO Not enough of those.
Quantify your fears. It is a simple yet powerful technique. This TED talk from Tim Ferriss might help.
Using the smallest sizing possible find some way, any way to become consistent - that can be a particular market, a strategy, a technical set-up, some sort or inter or intra-market correlated relationship, a machine learning program ... the path to consistency could entail any number of things. Once you find that consistency, everything opens up for you. Leverage, equity compounding, attraction for outside capitalization, you name it. Look for cause and effect. You can start with ten shares of a stock. Make the sizing small enough so as the emotional aspect of holding a trade (anxiety) does not impair your trading strategy.