Another question about training?

Ok, so I've been spouting verbal commands as well as using hand motions i.e "SIT" and I'd point to the ground with my right hand.... i am confused by clicker training...... is that where you buy a clicker and each time they do something correctly you click it and give them a treat? that way they ociate the click with doing something correctly? what do you feel is the most effective way to teach commands? verbally? or with hand signals? i'd prefer to attempt both... will it be too confusing to teach both at the same time? and if i do will they understand one or the other without combining both? i'd like to teach them many-a-tricks without hiring a professional, i've been looking at a bunch of websites from my previous post. Any more help would be mucho appreciated :)