First of all I would like to state that I am a low silver player so you should probably take what I have to say for a grain of salt. However I have successfully played a handful of the champions that you listed and maybe I can help a little.
For Ivern, generally I will try to invade and take his first buff then go back and get my buff on the corresponding side. After that try to gank whatever lane you happen to be closest to if it makes sense. Then just repeat. Take enemy buff. Take your buff/some of your camps. Gank lanes. Repeat. He is a fun champion who feels kind of like a second support in the jungle and I know some say he isn't strong but he has a high potential to benefit your team in ways other than doing tons of damage.
For Bard, honestly just try to have a good time. I am pretty sure you only want to pick him with an adc that can hold their own in lane and not die the second you leave as you need to collect chimes to become stronger. I try to pick up chimes after backing and heading back to lane or when setting up wards for objectives. The best way to play Bard is to have fun and be as annoying as possible by landing stuns that the enemy doesn't expect and ganking when the enemy is playing aggressive. He is also really fun if you have a duo and they play kayn.
And finally for Malzahar, press R and don't die a lot.