Wilson graduated from Victory Christian Academy. He spent 20 years with the Birmingham Department of Public Works and as a substitute teacher and volunteer assistant football coach for Birmingham City Schools. He has been a parent-community coordinator for Wenonah High School and president of Community First Birmingham and the Southwest Alliance Association. He has also served as recording secretary for Laborers' International Union of North America Local No. 559. More recently, Wilson has hosted a weekly talk show, "Sunday Conversation with BigWalt," broadcast on WJLD-AM and WJLD-FM.
Wilson is a former president of the East Brownville neighborhood's advisory board. He was an unsuccessful candidate for Birmingham City Council in the 2009 Birmingham municipal election. As a candidate he pledged to represent District 7 and work to reduce crime and revitalize neighborhoods. He garnered 6% of the votes in a race won, in a runoff, by Jay Roberson.
Wilson was elected Constable of Alabama House District 57 in 2012. He did not challenge Roberson in the 2013 or 2017 elections. Instead he ran for a seat on the Board of Education in 2017, and was defeated by Patricia McAdory in a runoff.
When Roberson resigned in September 2018 to move to Alabaster, Wilson applied for the Council's appointment to complete his term. Wardine Alexander, who had finished third behind Wilson in the 2017 school board election, was appointed instead.
Wilson and his wife Brenda have two children, Jacenta and Walter Jr. The family attends Hopewell Missionary Baptist Church in Hillman Station. He is also a member of Woods Joy Lodge No. 752 of the Most Worshipful Prince Hall Grand Lodge, Free and Accepted Masons of Alabama.