Start with basics 
https://www.cryptocompare.com/mining/calculator/eth?HashingPower=20&HashingUnit=MH%2Fs&PowerConsumption=140&CostPerkWh=0.12
See what's hot right now, try to calculate losses and profit, like you would if you were calculating your taxes (that's a good practice). It's all just thoughts and words, unless you place the numbers on a piece of paper
https://www.cryptocompare.com/mining/calculator/eth?HashingPower=20&HashingUnit=MH%2Fs&PowerConsumption=140&CostPerkWh=0.12
See what's hot right now, try to calculate losses and profit, like you would if you were calculating your taxes (that's a good practice). It's all just thoughts and words, unless you place the numbers on a piece of paper