- Present progressive tense, past progressive tense. ("stare" plus the gerund). You can always use the regular present tense to say what you are doing right now. But the present progressive tense is becoming more widely used in Italy. It is only used to talk about an action that is happening right now.
Conjugate stare in the present tense, and add the gerundio. The gerundio is formed by taking off the infinitive endings and adding these endings:

-ire         >         -endo
-ere         >         -endo
-are         >         -ando

To say that you’re doing something right now,  use   Stare + il gerundio

The gerund is formed by dropping the infinitive ending (-are, -ere, or –ire) and adding –ando for –are verbs and –endo for –ere and –ire verbs.  Some verbs have irregular gerund forms. (Notice how these have the same stem that they use in imperfetto.)

 

bere  to drink

bevendo

porre  to put, to place

ponendo

dire  to say, tell

dicendo

produrre  to produce

producendo

fare  to do, make

facendo

 

 

 

The gerund form does not change;  it always ends in –o.           examples:

Sto bevendo.  I’m drinking.

Stiamo mangiando. We’re eating.

Stai parlando.  You’re talking.

State uscendo.  You (plural) are leaving.

Sta arrivando.  She’s arriving.  (he, you)

Stanno camminando. They're walking.
 
In questo momento...
I am looking for my book. - Sto cercando il mio libro.
Why are you crying? - Perche stai piangendo?
She is opening the window. - Sta aprendo la finestra.
Usually the object pronoun is placed before stare:
Lo sto facendo! (I'm doing it!)
Mi sto alzando! (I'm getting up!)


- Past progressive: You can always use the imperfetto to say that you were doing something at a given moment in the past, but another way of saying it is by conjugating stare in the imperfetto, and adding the gerund.
I was talking to Giorgio when the bus came. - Stavo parlando con Giorgio quando è arrivato l'autobus.
Maria was playing the guitar at eight o'clock. - Maria stava suonando la chitarra alle otto.
(note: the progressive has a far more restricted use than the English form "was ___ing". It cannot be used to express a state, it must emphasize an action in progress. i.e. You cannot use it to say "She was wearing a dress." or "The sun was shining." or "What are you doing tonight?"