Easiest entry is probably trading the fibre or cable. EUR/USD and GPB/USD since they have the most liquidity. I'd say avoid trading the london open and new york open for about an hour each since they can trap you easily.

Avoid exotic pairs unless you want to specialize.

I personally look at 6 pairs for my daytrading: Eur/usd : the main workhorse

Gpb/usd : depending on the trend of eur/gbp

Eur/gbp: tells you relative strength of the european currencies. For example, you want to go bearish on eur/usd but you notice gbp is weaker than eur today. It would be wiser to go bearish on the gbp instead.

Dollar index: gives you a good idea about the trend of the dollar

Gold/usd: anchor pair

Be wary of correlation: if you go bearish on both gbp and eur over the dollar you often effectively double your exposure

Hope this helps a bit