It is important to feel good about your body. This does not necessarily mean having and wearing a perfect body, but accepting and loving the body that one has, without feeling the pressure or the demands of advertising or fashion that often raise physical stereotypes that are not real. This is something basic to be comfortable, to undress without problems in privacy.
In order to feel more secure in the sexual encounter, it is also vital to know your own body, your sexual responses, what you like and what you do not like. And the best way to get all this is this is through masturbation.
Another way to boost erotic self-esteem is to gain more knowledge about sexuality. And the best way for this is by educating yourself through reliable and good quality information sources.
Communication with the other person is vital, but it has to be an assertive communication, that is, it does not come in the form of criticism or offense. Always the idea is to propose or suggest what one wants and does not want, but in a good way.
It is better to have real expectations, to see sexuality as a way to enjoy and have fun. That sex has nothing to do with reaching goals or with self-demand. In this sense pornography can do a lot of damage. That is to say, there is no problem with watching pornographic films, as long as we do not think that what we see there is reality neither a documentary, but mere fiction and sexual fantasy.