Get to Israël by plane! Be prepared to a high security. People are going to ask you were you are gonna stay/were you stayed. Make sure you have prove of where you stayed when you get back home!
By bus ofcourse and otherwise try hitchhiking. But watch out, you can't trust everybody! Israelian police often stop Arabians by the way, so you better not hitchhike with them (no offence). Also don't talk about political things, because the driver might start arguing. When the driver brings up political things, just talk about another subject, say he is correct (even though you don't think the same)or tell that you don't know. Watch out for some taxicabs. They drive dangerously and will rip you off. The bus is the best option. The bus brings you from Tel Aviv to Jerusalem quickly and safe (most of the times anyway).
By plane. From Holland you can fly by KLM (Royal Dutch Airlines) or Air Holland. You will land at the airport of Tel Aviv. On the picture: me at the airport.