what would indicate to u that it will go down in the furutre
In order to help you decide, you need to understand technical analysis. Its a big topic but can be learnt. no one knows which way its going to go in the future, but we as traders analyse the charts using patterns, price and time and then place a trade based on our analysis of the underlying stock or indices.
A good place to learn TA is ITMS here:
InTheMoneyStocks - Technical Analysis Trading | Stock Market Chat Room | Learn to Trade
Hope this helps?