I would recommend using Bittrex, The Next Generation Digital Currency Exchange. Bittrex interface is very much user-friendly and super easy to understand. As they say, even my Grandma can use it. I seem to find it very pleasing and clear.
To go short on Ethereum, simply open an account with Bittrex and transfer some BTC into your a/c, go to BTC-ETH market and buy when the price is low and sell when you can profit on the market price prevailing.
There’s literally ‘no best way’, but overall the question of ‘when’ is important. You should know “when to act” and that comes with extensive knowledge, awareness and of course these candles.
Get yourself acquainted with it. I would recommend to set your chart to minimum 15 minute window.
You can use Bots to do the trading for you while you enjoy. I have never used Bots but those who have used, seems to be happy with it. The best so far is said to be, GUN BOT.
Here’s a YouTube tutorial on GUN BOT:
For some of my other related answers visit https://steemit.com/cryptotrading/@ghayas/what-is-the-best-strategy-for-reinvesting-daily-profit-from-crypto-currency