How to actually learn it

Two methods do almost all the work: learn a few characters at a time, and learn them at full speed with long gaps rather than slowly.

Learn at full speed from the first character

Slow morse teaches you to count dits, and counting is a habit that has to be unlearned before any real speed is possible. Farnsworth spacing avoids that trap entirely: characters are sent at eighteen or twenty words per minute from the start, and the gaps between them are stretched to make the overall pace manageable.

Two characters at a time, until they are automatic

The Koch method starts with two characters at full speed and adds a third only when you are reliably getting about ninety per cent of them. It feels far too slow for the first week and then overtakes every other approach, because you never build a lookup table you later have to discard.

Sending and receiving are different skills

Being able to read morse does not mean you can send it: the timing has to come from you, and a dah held slightly short reads as a dit to everyone else. Practising on a key with a live decoder is the only cheap way to see what you actually sent rather than what you intended.

Questions

What is Farnsworth spacing?

Sending the characters at full speed while stretching the gaps between them. It exists because learning morse slowly teaches you to count dits, and that habit has to be unlearned before any real speed is possible. Learning the character sounds at 18 WPM with long gaps means never having to relearn them.

How fast is 20 words per minute?

A dit is 1200 divided by the speed in words per minute, so at 20 WPM a dit is 60 milliseconds and a dah is 180. The standard word is PARIS because it is exactly 50 units long, which is what makes words per minute a precise measure of morse rather than an approximate one.

Do I need an account?

No. Translating, the practice key, the microphone decoder, the light output and the whole reference all run in your browser with no account and no limit. An account exists for two things: syncing your learning progress, and sending a message to a paired device.