In the past, exposure therapy was combined with relaxation exercises or breathing techniques to teach people how to calm themselves in situations that they fear.
However, this is being phased out of the most up-to-date treatment clinics because therapists and researchers have found that when people are focusing on relaxing, they are not focusing on doing the exposure as much as they could be, and the result is that the exposure has to last longer to be effective. However, if you are trying exposure on your own, relaxation techniques might be helpful in getting you through it at first, but you will want to move gradually toward exposures without the relaxation.
If an exposure seems too hard, instead of distracting yourself from it with breathing techniques, it would be best to just break the exposure down into easier steps and do it that way. Then you are exposing to the fears without any kind of distraction.
Also, it may be beneficial to have someone who knows about your OCD check in on you. This will help keep you accountable to your own therapy. Also, be sure to write down the things on which you want to work. Sometimes just getting the obsessions out of your head and on paper can help to lessen their effect because once they are written, you can actually see how irrational many of them are. In your head, because you are so used to them, they may make perfect sense.
Finally, be true to yourself, in the sense that you will need to be serious about therapy. Saying things such as, “Today I will just do my rituals, but tomorrow I will go back to challenging them” is just going to make your OCD worse and will set you back. Be sure that you are always challenging the OCD, no matter what.