What is the Best Option for my Crooked Teeth? (photo)

I am very self concious about my teeth. First is the crooked and crowding of both of my upper and lower jaw front teeth. Secondly, I have a partial denture on my upper jaw due to my tooth having fallen out as a young child, with no growth of an adult tooth. I am now of age and eligible for a dental implant or bridge..What are my best options? I have been thinking invisalign, veneers, bridge, or implant. I am looking for the cheapest route as I am not covered by insurance and am so young!