I am looking to get a tattoo in remembrance of my grandmother, and I want to be sure that I have the correct translation.

na zawsze w moim sercu

Would that be the correct translation/use of polish characters? Any help would be greatly appreciate
What does the "na" translate to? Is it necessary?

I am looking to get a tattoo in remembrance of my grandmother that would be the polish translation of "love always". I have come across the following variations:

kocham na zawsze
kocham zawsze
miłość zawsze
miłość na zawsze

Of course, because it is something so permanent, I want to make sure that it is the proper translation/use of the polish characters. Any help/suggestions would be GREATLY appreciate. Thanks so much in advance!

Hey, I hope you have a lovely time in Poland, and I will be thinking of you whilst I’m here. Don’t forget the picture of Kooka and some Polish snow. I wanted to give you something better than a CD, but we both know how that turned out! Enjoy the music.

I really want to write this correctly, including polish characters like ąćęłńóśźż if they are needed. Please don't use any online Polish translators, thanks