ESP8266 ESP-13 WiFi Shield doesn't react on any serial communication

Using Arduino Networking, Protocols, and Devices
1

Hi all,

my new ESP8266 ESP-13 WiFi Shield doesn't react on any serial communication. I tries to connect it with cables from:
GND to GND
5V to 5V
RX to RX0 (ESP-13 Side)
TX to TX0 (ESP-13 Side)

If i press the RST-Button on the ESP-13 Shield, i get this:

[serial garbage]
Ai-Thinker Technology Co.,Ltd.

ready

But if i enter any AT-Command like "AT" or "AT+GMR" it does not send any answer back.
Instead there is a WLAN Network called "AI-THINKER_D490B7" without password. When i enter it and try to connect to "192.168.4.1" i cant, because there seems to be nothing.

Please help