Volunteer for Hashem
A person worried about the weight of mitzvos can simply volunteer each morning, a little at a time.
A man new to Torah once told Rav Ben Tzion that he feared the mitzvos would be a burden too heavy to carry. The Rosh Yeshiva told him there was no reason to feel pressured. Each morning, he said, do not obligate yourself; volunteer. Offer to wear tefillin, since it is not so difficult, and he demonstrated how. Then offer to daven, with a little more added daily. To serve in Hashem's army of volunteers, he said, is an honor. The same joy shaped his halachic teaching. Teaching that one may not ask a non-Jew to extinguish a blaze on Shabbos even if every possession is lost, he explained that a Jew should sing and dance at the chance to love Hashem with all his me'odecha, a word the Sages read as including one's possessions.
Source: Yated Ne'eman feature on Rav Ben Tzion Abba Shaul (sayings recorded in his name); the printed source in his seforim has not been located.
Pick one mitzvah that has felt too large and offer it to Hashem for today only. It might be a short tefillah said with care, a page of learning, or an act of chesed you usually postpone. Say to yourself that you are not obligating yourself forever, only volunteering this morning. Then do it gladly, with a little song if you can. Tomorrow you can volunteer again, and a little more. Serving Him this way feels like a privilege and not a weight.