Verb conjugation of "tun" in German

Dear Maximilian, I look forward to your visit in Switzerland. After a somewhat difficult start, it seems that we have increased the website traffic and we are starting to receive more visitors.
I looked at your site on the Internet. It is very beautiful, the graphics are interesting and the site leaves a clean impression. I think that paintings and art in general are very interesting.
I am in my German lesson and I'm learning about the subjunctive. I had never heard about it before. Can you ever deal with all Verb conjugations? I just totally misunderstand the past tense!