Charge until the phone tells you to take the charger out. Use the phone normally until the phone tells you to charge it. Do that for 3 full cycles. Then you won't be back in a year complaining that your battery is dead.
And NEVER bring it down to 1%. A few more minutes and the safety circuit inside th battery opens up, and your battery becomes toxic landfill. Charging a completely dead lithium battery is extremely dangerous (as in fires and explosions - ask Sony about burning batteries), so there's a circuit in the battery that disconnects it from the world if you discharge it too far.
Trial runs have shown (see Battery University for the studies) that the longest life occurs when you charge the battery (except for the first 3 runs) when it gets down to about 50% charge. I can attest to that. My Motorola V551, made around 2004, still runs on its original battery, It's my "pop in the SIM and go" phone when my daily driver has a problem. Ten years (or more - I might have grabbed in the fall of 2003 - I don't remember when it was released) and after sitting for about a month, I just turned it on to check the battery - full bars.