Aspects of Action

To express an action that is planned (going to happen): ir a + infinitive. Voy a acostarme. I'm going to go to bed.
To express an action that is just about to happen: estar a punto de + infinitive or estar para + infinitive. El avión está para aterrizar. The plane is about to land.
To express an action that repeats: volver a + infinitive. Vuelve a escribir su nombre. You write your name again.
To express an action that has just happened: acabar de + infinitive. Acabo de llegar. I just arrived.