Given the low liquidity present in pre-market trading, I was wondering how difficult it would be to get filled on various sector and index etf's. How would I go about placing an order, and how early would I have to do so to ensure i get filled? Excuse my ignorance and thank you for the help!
Market for US ETFs is open from 04h00 - 20h00 EST, Monday - Friday. Market orders won't work out of the main session. To get filled, just place a sell (buy) limit order at the bid (offer) price. Or play market maker yourself, and wait for someone to take the other side of your order.