1. Clear all your browser cache before start booking
2. Don't use internet explorer. site response will be slow in internet explorer
3. Try to book from the machine running in ISD time, There is a possibility to get delayed due to following reason if the request is coming from outside india.
   i . Relay token due to time delay
   ii. Active Routes
4. To get to know the exact railway server time use following link and give any train number ex:14553http://www.indianrail.gov.in/train_Schedule.html. Sever time will be displayed in the bottom of the result.
5. We can use some tools to prefill the passenger information so that we can save the time during tatkal booking.https://addons.mozilla.org/en-US/firefox/addon/autofill-forms/. Chrome also has some extensions to auto populate the data.
6. Don't use the same user id with different session(either same machine two browsers or two different machine) it will log out other session.
7. During Tatkal time more than two tickets is not possible for one IP. If your using office internet best of luck.
8. During the booking process if the page is keep rotating more than certain time don't wait till the response comes. Stop and relogin this condition applies except payment page.
9. We have an issue with session expiry if we keep the page idle for some time. In order to avoid that issue keep click some date selector but please don't refresh the page.
10. During tatkal time IRCTC introduced new light weight pages for faster response. Please make sure that your using light version of the website.
11. Don't refresh your page after payment is taken from your bank, some case it takes time to get the confirmation from IRCTC.
12.Some features will be missing in the website during tatkal time to make it light weight.
13. Please don't do multiple refresh there is a limit configured
14.Happy ticket booking !!!