I sent this as a PM to the OP, but I'll post it here too.
1) As a Singapore national you don't need a visa to enter Switzerland either short or long term. However, for stays of over 90 days you do need a pre-approved permit
from the Zurich canton migration office so you should get in touch with them about what you need to do.
"Nationals of the following states do not require a visa to enter Switzerland under any circumstances: Brunei, Japan, Malaysia, New Zealand and Singapore.
However, the competent Swiss authority will issue a prior authorisation of a residence permit in the following cases:
a) for a stay of more than 90 days, or
b) a stay involving gainful employment:
lasting more than eight days, or
from the first day of work in the primary or auxiliary construction sectors, the hospitality sector, industrial or private cleaning services, surveillance and security services, itinerant sales and services or erotic services.
This prior authorisation of a residence permit is issued directly to the foreign national, or to a third party (employer), by the cantonal migration authority. The Swiss diplomatic or consular mission is not involved in this procedure." https://www.eda.admin.ch/countries/n...n-eu-efta.html
Migrationsamt des Kantons Zürich
Tel.: 043 259 88 00
Fax: 043 259 88 10 Internet
2, 3 & 4) there's no point in doing anything until you get your pre-approved permit. As a non-EU national you're last in the hiring queue otherwise and you don't have sufficient qualifications/experience to even be worth going through the non-EU hiring process for, sorry. https://www.bfm.admin.ch/bfm/en/home...zulassung.html
Once you have your permit though you can apply for jobs here without problems as you already have your permit.
5) Slow and time consuming. You'd need to prove the relationship is a long term, committed one that has already lasted several years. Expect to be asked a lot of very personal questions.