Install is simple, you need to setup and properly configure alsa, then you can just build and run pocketsphinx

sudo apt-get update
sudo apt-get upgrade
cat /proc/asound/cards

check your microphone is visible or not and if on which usb extension

 sudo nano /etc/modprobe.d/alsa-base.conf

Now change this

 # Keep snd-usb-audio from being loaded as first soundcard 
 options snd-usb-audio index=-2

To options snd-usb-audio index=0

if there is some other options snd-usb-audio index=1, comment it out

 sudo reboot 
 cat /proc/asound/cards 
 check your device is at 0
 sudo apt-get install bison
 sudo apt-get install libasound2-dev

download sphinxbase latest , extract

 ./configure --enable-fixed
 make
 sudo make install

download pocketsphinx, extract

 ./configure
 make
 sudo make install
 export LD_LIBRARY_PATH=/usr/local/lib 
 export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig

Run it, should work

 pocketsphinx_continuous -inmic yes