Template based on Helix Ultimate, like any other template, includes .ini file which contains all of the English terms that we used: language\en-GB\en-GB.tpl_unei.ini

Step 1:
Install Joomla translation for your native language, make it active.

Step 2:
Change the filename keeping original template name, for example:
from: en-GB.tpl_unei.ini
to: xx-XX.tpl_unei.ini

Where xx-XX is a LANG-PREFIX, for example, es-ES – for Spanish (Español), nl-NL – for Dutch, ru-RU - Russian, de-DE - German, etc.

Step 3:
In most cases, you should translate selected strings (used on front-end) to your language and save them with native language prefix. Each translated string must always be enclosed by double-quotes. File (.ini) must be saved as UTF-8 without BOM encoding. Inside you can find phrases for new addons. Example phrases:

 ;Custom Login
HELIX_REGISTRATION_TITLE="Register Now"
CUSTOM_LOGIN_HEADING="Sign In"
CUSTOM_LOGIN_HI="Hi"
HELIX_ULTIMATE_STICKY_LOGO="Sticky Logo"

;Product Slidshow Addon
COM_SPPAGEBUILDER_ADDON_PRODUCT_SLIDESHOW="Product Slidshow"
COM_SPPAGEBUILDER_ADDON_PRODUCT_SLIDESHOW_DESC="product slidshow with modal"
COM_SPPAGEBUILDER_ADDON_PRODUCT_SLIDESHOW_VIDEO_URL="Modal Video Url"
COM_SPPAGEBUILDER_ADDON_PRODUCT_SLIDESHOW_MODAL_CONTENT="Modal"
COM_SPPAGEBUILDER_ADDON_JS_SLIDER_SHOW_ONLY_CONTROLLER="Show only for controller area"

;Unei Blog
HELIX_ULTIMATE_PUBLISHED_ON="Published On"
HELIX_BY="By"
HELIX_ULTIMATE_SHARE="Share"

;Unei J2Store
J2STORE_CART_LINE_ITEM_ACTION="Action"