JUNGLE
So needing tips for Elise and gragas I understand they are complete two different kinds of mech and champs but some help would be greatly appreciated
4 Comments
Both have high skill caps (that's really all I know about Elise).
For Gragas, the most important thing is using your ult properly. You can do things like body slam and ult them back at the same time or just straight up ult them back into a charged q. Body slam+flash is another thing you should practice.
I don't see why someone would downvote you for asking for help, but they did.
Now, while I don't play either of these champions very often, I do own both and have been playing for 7 years, so I know mostly what they do.
Elise: Elise is a very fun and interesting champion who has extremely strong early ganks. As early as level 3, you have access to your full kit and 6 spells, which is incredibly powerful. Gank early, gank often is the key to winning with her.
Start with your W; the damage from it in human form is decent, but the attack speed steroid and healing in spider form is the reason why you start it. It allows you to clear more aoe-oriented camps, like Raptors, early.
Pick up Q at level 2 and E at level 3. Max Q first, then W, and finally E Your clear should look somewhat like this: Blue -> Raptors -> Red -> gank.
When ganking, initiate with your Cocoon for the stun, unloading your full human form combo as fast as you can before switching into spider form and Rappelling onto them. In the duration of the stun, your ally should be able to deal some decent damage to them as well. After landing on them, use your Q when they're really low health; spider from Elise's Q does a good chunk of % missing health damage, while human form's does % current health, so you want to hit them with human Q first and spider Q last to maximize your damage.
Elise can also use Rappel to reset turret aggro in the case of a dive. You can target the ground to go up and reveal the entire area of effect, allowing you to make for some quick and easy getaways over walls if there's something on the other side for you to drop down on.
For build, go 
and then tanky stuff. You'll deal decent burst and sustained damage while being tough to kill.
Gragas:
Gragas is one of the champions I've played the least in the game, so I will admit that I'm not the most knowledgeable on him. The best tip that I can give is that his Q does more damage the longer it charges and you can flash while dashing with his E to reposition the knockup on the fly. Sorry that I can't be as in-depth with him as I was with Elise.
Brutal helped you w/ elise, i dont know elise but i know gragas lol.
Basically w/ gragas you want to take either Q or W first depending on what camp you are starting. B/c of his aoe gragas can start at a number of camps successfully. If you have a midlaner w/ aoe (galio Q, lux E) starting raptors works really well w/ a 1 aoe spell leash from mid, then go to red then blue and look for a gank.
When ganking you want to W before you E in for the extra burst/aoe, save your Q for the slow for when they try to run or throw it out during the combo in the path they would run away (can force a flash or secure the kill w/ charged up Q damage).
Your ult is probably your biggest point of skill expression and will take a lot of practice to get the most out of it, a great combo is bodyslamming in and ulting behind the stunned target to knock them back into your team/turret, gragas' CC makes him very good at coming in as backup on an enemy gank/dive to turn it around. And as someone mentioned before, his bodyslam flash is a very strong combo that increases the range of this CC to create very strong ganks out of fog of war. Ult can be used for engage or disengage but as said it takes practice, missing ult feels bad and knocking the enemy tank (or diver) into your backline feels even worse.
As far as build goes gragas is versatile he has strong base damages so he doesn't NEED early ap, good sustain in his kit and some tankyness as well. If you are the main tanky champ on your team you can build full tank, but if you have a maokai top for example you can comfortably build more of an ap bruiser build including 
adding damage to your ganks while still being hard to kill.