Tomorrow, 2 August, you can gain a plenary indulgence under the usual conditions (see below) by visiting a parish Church and there reciting the Our Father and the Creed. This is called the Portiuncula indulgence and goes back to St Francis of Assisi. Fr Z has the details.
Don't forget that you can also gain a plenary indulgence by visiting a Church on the day of the titular feast, and there reciting the Our Father and the Creed. I made a list of other indulgences: please see the post Plenary indulgences for particular days which has a link to the list. The post has some background information which you may find helpful since indulgences are not well understood today - which is not surprising since indulgences are not included in most Catholic education curricula, and most priests never preach about them. Therefore many Catholics are left with whatever silly, half-baked, ill-informed nonsense about indulgences happens to be current.
If you want to understand the theology of indulgences, I recommend reading the first four chapters of Paul VI's Indulgentiarum Doctrina. By reading and digesting not much more than 3000 words, you will gain a balanced and theologically mature understanding of indulgences. In fact, since few people (including priests and bishops) seem to think it worth the bother, you will instantly become relatively expert on the subject!
To forestall the common objection that almost nobody ever gains a plenary indulgence because of the condition about being detached from venial sin, please see my post: Plenary indulgences not impossible. This post also gives general information about the conditions for gaining a plenary indulgence.