From I35:

Heading South:

Exit on 1431 (exit #256)

Turn right onto 1431

Turn left onto Parmer

Turn left onto Avery Ranch Blvd...

Heading North:

Exit on RR-620 (exit #252B)

Turn left onto 620

Turn right onto Parmer

Turn right onto Avery Ranch Blvd...

From Mopac (Loop 1):

North on Mopac until TX-45 west

Exit Parmer

Turn left onto Parmer

Turn left onto Avery Ranch Blvd...

From 183/183A:

Exit Avery Ranch Blvd

Turn East onto Avery Ranch Blvd

Continue until you cross Parmer...

...From Avery Ranch Blvd:

Turn left onto Avery Club Drive

Take second left onto Sunningdale St. 

Arrive at 15316 Sunningdale St.