Why do people close their eyes & start praying with closed eyes when they are in front of their revered God in the temple or church? Simple answer to this is that they feel God much closer to their heart inside themself than in the standstill figure or statue in the temple or church. Yes, God is there in your heart who is sitting silently over there watching you & your actions. This aspect of God is called "Antaryami".
"Antaryami means the one who can observe & know every thing of your heart without you being explaining anything to Him. So God is called Antaryami as we need not explain to Him about any of our problems. In this aspect He is Antaryami & He knows what we want."
Below verses of Bhagwat Gita explain this aspect of God only:
"jyotisam api taj jyotis
tamasah param ucyate
jnanam jneyam jnana-gamyam
hridi sarvasya visthitam" (Bhagwat Gita: Chapter Thirteen verse 18)
"Sri Krishna said: O Arjuna, He is the source of light in all luminous objects. He is beyond the darkness of matter and is un-manifested. He is knowledge, He is the object of knowledge, and He is the goal of knowledge. He is situated in everyone’s heart."
hrd-dese ’rjuna tishthati
yantrarudhani mayaya" (Bhagwat Gita: Chapter Eighteen verse 61)
"Sri Krishna said: O Arjuna, The Lord / Supreme God dwells in the heart of all beings, who are mounted on the automation of this body, causing them by His illusive power of material energy to revolve (according to their actions) and is directing the wanderings of all living entities."
So when God is there in your heart in "Antaryami" aspect then you can always find daily some time from your daily routine & can pray to Him in your home only, while closing your eyes, sitting in a lonely peaceful place. Daily praying to Him like this shall make you more peaceful & shall make you feel more closer to God. A deer who is having the Kasturi (Musk) in his body only, searches for the cause of fragrance all over there in the wild, while that sweet fragrance is coming from the inside of his body only. Same is the case with us that we are searching for the God outside ourselves while He is sitting in our heart only.