the best lot value of forex trading is 0.01 and we use many sizes with our trading account balance and if we have a good account balance then we make large lot size in forex trading account and we use our lot size with low risk and we do not use a lot of large sizes that give you a loss in trading so firstly know risk management then use lot value in trading account I think it depends on the value you have in your account size, then take the risk 3 to 4 percent on it and accordingly set the size your lot for example if you have a 300 dollar account size then the maximum lot size will be. 10 lots. This way you avoid unnecessary risks in forex trading.