Create an account on Wikidata. If you have a global account, you will be able to login using your unified global ID.
Add your babel information on your profile. An example can be viewed here. This will help Wikidata to identify the languages which you are comfortable with.
Now, go to Reasonator. Reasonator is a tool hosted on wmflabs. Reasonator will help you to find out unlabeled Wikidata entries and help you to add the labels quickly. Search for the name of constituency or the candidate for election.
Click on the language icon on the top right of the reasonator to change to the language of your choice.
Now, search for the topics of your choice on the search box and identify the labels that are not yet translated to your language. Normally these will be in English and underlined in red if you hover over it.
Hover over the label which you want to translate to your language. An info box will appear which will prompt you to add the label in your language.
Click on the 'Add a label' link to be able to add the label in your preferred language.
If you do not yet have the 'WiDaR' enabled, the resonator will prompt you to do so. You can enable WiDaR by clicking on 'Authorize WiDar' option on this page.
You might have to refresh the Reasonator page to view the changes you made using WiDaR.
Please make sure that you have changed the list to your preferred language before you start labeling! You can change the language by clicking on the language icon on the top right of the page, adjacent to the search box.