Ensure the following addresses are configured correctly:
PC1 = 10.1.1.100/24 (GW 10.1.1.1)
PC2 = 10.1.1.101/24 (GW 10.1.1.1)
SW int vlan 1 = 10.1.1.11/24
Branch Gi0/0 = 10.1.1.1/24
Branch Gi0/1 = 209.165.201.1/27
HQ Gi0/1 = 209.165.201.2/27

SW1# show cdp neighbor
Branch# show cdp neighbor
Branch# show cdp neighbor detail
HQ# show cdp neighbor
HQ# show cdp neighbor detail
(observe the different connected neighbors for each device.)
***If CDP is not enabled, go to global config & type cdp run***

--- Checking routing table ---
Branch# show ip route
HQ# show ip route
(observe the Connected network for each router)

Branch# ping 10.1.1.100	(yes)
Branch# ping 10.1.1.11	(yes)
Branch# ping 209.165.201.2	(yes)

HQ# ping 209.165.201.1	(yes)
HQ# ping 10.1.1.100		(NO)
HQ# show ip route
(observe your routing table, do you see network 10?)
** If the routing table does not contain your destination, the ping will drop.**

--- Configure static route ---
HQ(config)# ip route 10.1.1.0  255.255.255.0 209.165.201.1
HQ# show ip route	(see the new Static route)
HQ# ping 10.1.1.100		(yes)

Common troubleshooting:
=> show run
=> show ip interface brief
1. Correct IP add & subnet mask for each interface
2. Make sure interface up, up	=> no shut

--- Remove static route, configure default route ---
HQ(config)# no ip route 10.1.1.0  255.255.255.0 209.165.201.1
HQ# show ip route	(noticed the Static route is removed)
HQ# ping 10.1.1.100		(NO)

HQ(config)# ip route 0.0.0.0 0.0.0.0 209.165.201.1

HQ# show ip route	(see new default route)
HQ# ping 10.1.1.100		(yes)

HQ# ping 10.1.1.11		(NO, because SW1 has no gateway)

SW1# show run		(absence of default gateway)	
SW1(config)# ip default-gateway 10.1.1.1

HQ# ping 10.1.1.11		(yes)

--- Adding a Server to existing Topology ---
Drag in a Server
Use a Cross cable to connect a Server to HQ Gi0/0
Server IP: 172.16.1.100/24  (Gateway: 172.16.1.1)

HQ(config)# int Gi0/0
HQ(config-if)# ip add 172.16.1.1 255.255.255.0
HQ(config-if)# no shut

Server> ping 172.16.1.1	(yes)

Branch(config)# ip route 0.0.0.0 0.0.0.0 209.165.201.2

*** PC1> ping 172.16.1.100 to ensure destination is reachable

--- Configuring PAT ---
Branch(config)# int g0/0
Branch(config-if)# ip nat inside
Branch(config-if)#int g0/1
Branch(config-if)# ip nat outside
Branch(config-if)#exit

Branch(config)# access-list 1 permit 10.1.1.0 0.0.0.255
Branch(config)# ip nat inside source list 1 interface g0/1 overload

PC1> ping 172.16.1.100
PC2> ping 172.16.1.100

Branch# show ip nat translation		(notice the same ip add is given to both PC)
Branch# show ip nat statistics
Branch# debug ip nat

PC1> ping 172.16.1.100	(debug only works when there are traffic related to its command)