Start your journey early in the morning from Delhi as Sariska is nearly 240 KMS from Delhi. You can explore multiple Dhaba's (so called Dhaba's as these are huge and air conditioned and serve everything you want to have from North Indian to Chinese) on the way.
Easiest way to reach there is by road only but you need to make sure that you don't miss the diversion which leads you to your destination. (Use the navigator).
It will be a tiring day for you so better to stay at a nearby resort or hotel. You can opt of the newly opened Gulmohar Sariska (a bit away) or the closely located Sariska Palace.
Have your breakfast and then head towards the Sariska Wildlife Sanctuary. You can hire the Jeep or take your own car if they are allowing at that time. Try your luck in exploring the place and sneak peek with the tigers.
You can also visit the Pandupol temple inside the sanctuary.
After having a refreshing sleep and tasty food you can head towards exploring the nearby places like the ancient bhim temple, the Hanuman temple (one of the places where Karan Arjun movie was shot) Ek Munda song. Check out..
Visit Viratnagar, Jaipur district where you can eat lots of amazing food. Don't miss to have these - mava kulfi, aaloo pyaaz kachori from jodhpur mishthan bhandar, dahi pakodi and moong ki daal ke pakode. Trust me it's finger licking good.
You can head towards Bhangarh (The haunted place) which is around 60 KMS from there and then back to Delhi.