first and foremost you have to have the knowledge yourself. you have to know what you are talking about and ensure that you are taking this knowledge from reputable mashayikh and sources. if you dont, you risk raising the child believing and practicing the wrong things.
secondly, best way to teach someone is by teaching them according to
their level of understanding and mentality so you have to "shrink" down the big information because it is sooo pointless to teach a child say tawheed by opening say kitaab ul-tawheed and reading it off to them. they dont get because its not how their brain works.
no, take the information/main point from the book and as i said "shrink" or "mould" it to conform to
their level of understanding.
teach them the seerah/stories of the prophets. people can and will relate to one another and children are no different so when you tell then that the Prophet's (sallalahu aleyhi wa sallams) parents died when he was very little they will feel sorry for him/sympathies with him because they know how much they love
their own parents and through this means a love and respect will inshallah develop and hence this may be a foundation to following his sunnah.
be kind, understanding and a gentle teacher.
dont make up answers to the questions they may ask. seriously know your stuff. and if you dont know just tell them that you will look it up and this way you're teaching the importance of asking (an imam) when they dont know.
make sure you are practicing what you preach so that they genuinely look up to and so that you avoid teaching them hypocrisy
always be encouraging, listen to their ideas and disagree politely as to not make them feel dumb.
if possible, teach them with other kids so that they have someone their own age to relate to. i mean consider the age gap between you and them...it maybe about 20 years or something so they may not be able to relate to you and get restless, etc.
if a child's parent/s arent practicing, or dont do something right, preach to them as well because a child's parent/s are their role models. for example you can say to a child its haraam to.... but they may not listen to and if they do, they will be hesitant becuase they dont see that their own parents are practicing this certain thing, in fact they will probably turn around and tell you "but my mum does that" so they wont be very willing to listen to what you are telling them.
know when to be kind and when to be stern, avoid both extremes and seek a balance between the 2. with children they will say things innocently but even then, some things they ask (or even the manner they ask) isnt always acceptable. for example you may hear a kid speak ill of Allah. so in this case, you need to be stern. dont be scared that you being stern will put them off the deen and make excuses "oh they are just kids, they are not responsible for their actions just yet"!! dont do that!!! avoid it like the plague! their childhood is like the blueprint for their adulthood...if they cant get rid of this now or if they dont know this is wrong now, they will grow up thinking this type of stuff is acceptable!....no, as long as its in its right time and place, and done MODERATELY, it shouldn't be a problem, inshallah.
make sure they hang out with the right crowds and make sure they are in good (well mannered preaching) schools.
dont be afraid or dont scold then if they correct you. no encourage this and praise them when they do because they will respect you more and if they respect you more, they will listen to you more and also it will teach them to accept the truth no matter who it comes from.
make your relationship with them informal. dont always be so serious...joke around, take them out and in engage in dunya activities. when they see you are a spoiling, fun person, they will develop a love and respect for you, which will be a major aid in teaching them so in other words, make sure make sure they love you
have a routine and timetable for them and make sure they follow it. like reward them when needed, etc.
