Exotic and uncommon currency pairs should be avoided by novice Forex traders as some further knowledge is needed to trade such pairs successfully.
Here is the list of major currencies beginner traders should focus on:
US Dollar (USD)
British Pound (GBP)
Swiss Franc (CHF)
Japanese Yen (JPY)
Australian Dollar (AUD)
Canadian Dollar (CAD)
Also novice Forex traders should try to avoid currency pairs which have high spreads. Spreads vary from broker to broker.