I'll start off by saying that I am a Christian and I do believe in the Triune God mentioned in the Bible (Father, Son, Holy Spirit) and that he is the only true God, maker of us and our universe, and is our Saviour.
I'm not going to claim that I can "prove" God's existence, because I can't. It's a faith based belief, and I believe that God wants us to have faith in him rather than only believing in him if we were to physically sense him, and the "Doubting Thomas" story from the book of John comes to mind... "24 But Thomas, one of the twelve, called Didymus, was not with them when Jesus came. 25 The other disciples therefore said unto him, We have seen the Lord. But he said unto them, Except I shall see in his hands the print of the nails, and put my finger into the print of the nails, and thrust my hand into his side, I will not believe. 26 And after eight days again his disciples were within, and Thomas with them: then came Jesus, the doors being shut, and stood in the midst, and said, Peace be unto you. 27 Then saith he to Thomas, Reach hither thy finger, and behold my hands; and reach hither thy hand, and thrust it into my side: and be not faithless, but believing. 28 And Thomas answered and said unto him, My Lord and my God. 29 Jesus saith unto him, Thomas, because thou hast seen me, thou hast believed: blessed are they that have not seen, and yet have believed."
While God's existence can't be definitely proved until he returns to the Earth once again (if one needs to see/touch/hear him and etc.), I still have my reasons for believing that his existence is more probable than not, and they are in line with William Lane Craig's reasoning. The origin of the universe, the fine tuning of the universe, objective moral values, the story of Jesus Christ (life, death, resurrection), and my own personal experiences all make more sense to me when the Christian God is used to explain them.
I guess that would be my very brief view on God's existence.