No, there is no such thing as a “trial Catholic.” Either you choose to become a Catholic and live up to the responsibilities and consequences of that choice, or you do not. What you can do is, insofar as possible, to live as if you were a Catholic. That means you can attend Mass every Sunday and holy day of obligation (daily, if possible), pray as a Catholic (e.g., rosary, Catholic chaplets), go on Catholic retreats, wear a favorite Catholic sacramental (e.g., crucifix, saint medal, scapular), etc. You might also go to RCIA classes and to other Catholic adult education classes. The limitation, of course, would be that you ordinarily would not be able receive the sacraments, such as the Eucharist and confession.
Keep in mind that Catholicism is not a “lifestyle choice,” but a way of life. Catholics are called to be disciples of Jesus Christ, learning from Christ through the Church he established to teach in his name. Catholics accept “the rules” of Catholicism, not because they are unthinking or unreflective, but because they trust the Person who ultimately authorizes those rules. Ultimately, we are Catholics not because it makes us feel good or suits what we believe, but because we want to be good (i.e., virtuous) and to learn from our Lord Jesus Christ what he died to teach us.
