About promotion coupons

[Demow]

To get the coupon worth 100 Turkish Lira, we first make a 25 Turkish Lira AdSense expenditure, then enter the coupon code via email to benefit for free, am I understanding this correctly so far? Should we do this each time we open a new AdSense account or should we do it after both creating a new AdSense and email account? Also, assuming we have a promotional code, at which stage should we use it for the 25 Turkish Lira, and how should we use it? I'm a bit confused about this matter, sorry if I also confused you in the process.