We get asked a tonne of questions about brewing coffee. The most important thing is to get the basics right.
So, Basic Tip No. 1
It's essential to weigh your beans when brewing coffee. It's the only way you'll know how much water to use (i.e. to calculate your brew ratio) - and this is one of the key elements that leads to consistent results.
e.g. for most filter brewing methods, you'll use somewhere between 15-20g of water for every 1g of coffee.
You'll need scales that measure in 0.1g increments. You can pick those up very cheaply on eBay and the like (just search for jewellery scales). You'd be amazed at how much difference a few tenths of a gram makes!
Those plastic scoops you often get with coffee and coffee machines are practically useless - please don't, you deserve better.