Here are some great tips from lds.org:
Hurricane Harvey has ravaged the greater Houston, Texas, area, affecting thousands of people. Many organizations and individuals have provided rescue efforts and continue to help those with the greatest needs.
LDS Charities, the humanitarian arm of The Church of Jesus Christ of Latter-day Saints, is donating supplies to the relief efforts and is preparing to support ongoing relief and cleanup. This relief is provided through the Emergency Response efforts of LDS Charities, which responds to hundreds of disasters worldwide. LDS Charities’ first efforts are focused on helping people in need.
How you can help
As you feel a desire to provide aid, please consider the following seven ways you can help:
Don’t go to the disaster area until you are invited. LDS Charities works with government organizations that are already in place. If you want to immediately volunteer, connect with the local government emergency operations handling the situation or an organization in the area that is soliciting volunteers. Spontaneous volunteerism creates what is often called a “second disaster”—having to support the needs (shelter, food, safety, and so on) of additional volunteers with the same limited resources available to support those in need.