Here's a few tips since you haven't done GWD yet (Plus):
Never fight in the main arena to get kill counts; as you'll drain alot of health since all of the minions in the main arena hit randomly.
Hold a bandos item (If your doing bandos) so when you enter the chamber you don't get attacked by multiple targets.
Fighting inside the (bandos) chamber will only have minions to give you BANDOS KILL COUNT which is safer (recommended to do that)
Whenever you do kill count (as for me) never waste a single food when doing it, you'll need every single food at the boss.
Maximum strength gear you could use:You can use a slayer helm instead of nezzy, also angers work at General Graardor considering that his 'size' is huge.
As for amulet/cape, some people might not have them, so a cheap defensive cape and a normal strength amulet would be fine.
How your inventory should look like:EDIT: It's very recommended to go with a group of trustworthy players that requires 3+ players. Soloing is way too hard, unless your lucky with hits.