Usually vs Used to - Accustomed

English speakers usually have no problems with distinguishing between USED TO, USED TO DOING and USUALLY.

Unfortunately, this is not always the case with non-native speakers, especially Brazilians

You could attribute this perhaps, to what is really a false friend in the word ACCUSTOMED or acostumado in Portuguese. We are ACCUSTOMED TO DOING something is understood to mean usually or habitually by Brazilians when in fact it has quite a different meaning.

To be ACCUSTOMED to something or be ACCUSTOMED TO DOING something indicates the acceptance of something being NORMAL or USUAL (not repeated or habitual)

Compare the following;

                  - I USED TO go everywhere by bicycle, but now I use the Bus.
(I USED TO is a simple past tense structure and means that the statement isn't true today. I USED TO drink a lot of Coke. I USED TO smoke.)

                  - I AM USED TO RIDING around the city on Buses.
(Taking Buses is easy for me. I have no problem finding the Buses I need when I need them.
PLEASE note. The verb to BE (AM, IS, ARE, WAS, WERE etc,) means that the main verb MUST be VERB + ing - riding, taking, estimating etc)

                  - I AM ACCUSTOMED TO RIDING around the city on Buses.
(It is my CUSTOM to take the Bus when I go around the City. Sometimes I MIGHT take a Taxi, The Train or get a ride with someone, or even ride my Bike, but it is more NORMAL or USUAL for me to go by Bus.
PLEASE note. The verb to BE (AM, IS, ARE, WAS, WERE etc,) means that the main verb MUST be VERB + ing - riding, taking, estimating etc)

                  - I USUALLY RIDE around the city on Buses.
(When we want to express something that happens on a regular basis we always use USUALLY. I USUALLY work on Saturday`s, but not every Saturday.)

ALWAYS
Another problem similar to this is the use of `We all the time go to the Supermarket on Saturday`s`
Here, there is a teaching problem where the idea of always and all the time has not been explained properly.

The correct usage is `We ALWAYS go to the Supermarket on Saturday`
ALL THE TIME / THE WHOLE TIME refers to an extended period of time.

Compare - Stop complaining ALL THE TIME.
               - Stop complaining THE WHOLE TIME.
               - He is ALWAYS complaining.