You will need some equipment to tackle your weeds including protective clothing. Let's start with the basics...
From the top down:
Hat - don't be a skin cancer hero.
Long sleeved shirt and trousers - protect yourself from not only the sun but insects too. Sometimes we use specific 'work wear', sometimes we use old items that have gone past their use by date.
Footwear - we wear gum boots (wellies!), they are cheap, waterproof, tough and provide protection against potential snake bites.
Get yourself some decent gardening gloves, think of them as an investment rathar than a cost. After trying a number of various gloves from Bunnings and other hardware stores we found these heavy duty gauntlets which are fantastic. Even then, we go through at least one pair a year but they last longer than pretty much anything available locally.
Like most things, the quality improves the more you spend. However, we have lost so many pairs over the years (lost in the leaf litter etc) that you may find a cheap pair does the job just as well.
Long handled shears
Available from most good hardware stores and a good pair will last a long time if you look after them.
If you keep the above well sharpened you'll find most jobs become a lot easier.
Useful for removing large Gamba, Mission and Rat's Tail plants.
For collecting grasses which have been brush-cut.
Perhaps the most expensive cost you will encounter, we use a 12volt 25 litre Hardi for spot spraying. We can't fault its basic durability although the pump did fail after about eight years use. Replacement pumps cost hundreds of dollars - instead use a caravan pump from ebay for under thirty bucks. And you don't need a quad bike to deploy - simply put the sprayer in a wheelbarrow with a car battery. Simples.
Use a brush-cutter to reduce the amount of chemicals required for spot spraying. Do not contemplate buying anything from Bunnings but invest in a good brand that will withstand the rigours of rural life - we would recommend Shindaiwa, they are well-designed, tough and reliable.
For smothering areas of weeds - can be expensive but you can find cheaper alternatives using some lateral thinking.