Fundraising
If a charity, a foundation, or volunteering is too long of a time period for you to commit for, then think about a one-time fundraising event to build the kingdom of God. Jesus commends people for using their money wisely. This means that men of the kingdom should use funds wisely in order to build up the kingdom. The fundraising could be for a Christian cause that will change the world, or it could involve your local church. Another option could be to fundraise for a specific person in dire circumstances - maybe cancer has struck a family and they are having trouble with medical bills. Fundraising for a family in those circumstances would be a wonderful way to show the love of Christ.