Hi.. For that i advice you to see the real examples . means go to the site which are providing the online booking. See their working, how they work , from where the pages/forms are navigating.
See their data flows , their design, type of controls they have for particular data.
Then after understanding the whole system, you will get the idea what you have to do now.
1. Decide a pretty website template
2. Create the database structure, no. of tables you will need , data types of columns, relationships between tables etc
3. No. of webpages you will need
4. How the client will pay if they book ticket from your site etc
Hope this info will help you to start your Website