For professional results, use the right tools
To get professional results, you have to have great drywall taping tools. I love using my stainless-steel mud pan. I use a flexible taping knife that's just under six inches wide. Before I used it the first time, I used a metal file to slightly round the corners of the tool. Straight from the factory, these tools have very sharp corners that can cut into the paper tape as you strike inside corners when taping.
Some professional drywall finishers prefer to use trowels to apply mud. I started using broad knives 36 years ago and never gravitated to trowels like those you see a plasterer use. I have a 10-inch and a 12-inch broad knife, both of them stainless steel.
Professional finishers who tape entire houses in one day will use a tool called a banjo. This handy tool applies the exact amount of mud to the tape. The best analogy I can offer is those packaging taping machines that apply clear tape to cardboard boxes. The banjo eliminates the step of you applying the mud to the wall because the tape comes out of the machine with the mud on it.
You'll discover countless other drywall taping tools if you visit a business that sells drywall and equipment to professionals.