Ms. Alias,

Actually, you can find bus that run from Badaling to Ming Tomb(Ming Dynasty Wax Museum). After you visit the wax museum, you may go to visit Dingling and Sacred Way.

I can conclude that

I should take the bus no.919 (slow line) from Badaling Station and get off at Ming Huang La Xiang Gong Station (The Ming Dynasty Wax Museum) to visit Wax Museum and/or Sacred way.

Then, I can take bus no.314 at Nanxincun (around Scared Way) to Dingling Tomb.

When I visited Dingling Tomb, I can take no.314 back to Changpingdongguan and continue to no.345 back to Deshengmenxi.

Is it correct?
How far away from Wax museum to Sacred way?
and How can I go faster to Beijing National Stadium (Bird's Nest) from Dingling Tomb?
Thank you for all answers.

Hi Alias,yes your route is correct.
Wax Museum is near the Scred Way. After visiting Dingling Tomb, you can take bus no. 314 to get off at Changpingdongguan and transfer to no.345, and then get off at Madianqiaonan. Here get across the road to take bus no.83 to the Bird's Nest.
BTW,Alias, are you sure to make all of these spots in one day? That will be very busy for you, especial the seniors. I recommend you not go to the Wax Museum, but you still need to start before 6:30 i'm afraid.
good luck!

Thank you, Mr.Sail. Your comment was very helpful.