Sindarin Imperative - Hope! Doom!

It's been a while since I have worked with Sindarin. I would like to work out the sindarin text for a tattoo, so I'm hoping to get it plausibly right. I need the translations of both:

Hope (n) Estel

Doom (n) Amarth

I can see from this page that the imperative just means adding -o to the end of the verb, but I need to figure out how to make a verb out of a noun. Is that just 'estelio/estelya' and 'amario/amarya'? With the imperative, do we need more to the sentence? I am considering adding 'nartha-' to kindle to this somehow, but I thought I would start simpler.

I would say: Estelio! Bartho!

Estelia- means to trust or to hope, and bartha- means to doom. Imperative ending is indeed with -o

I see. Amarth and Bartha- probably come from the same root with that old MB prefix. I wonder if there is a better word for the kind of fate/doom I'm going for. I plan on working the 'doom' word into some Rohirrim art. So in that case, I wonder if we can widen the phrase:

cuil martho cuil [life] (m)bartha->o fated life. or would it be appropriate to pull from 'meleth marthannen' to make 'cuil marthannen' cuil marthannen? That's not imperative, but it might make more sense. What do you think?

I'd rather take "cuil marthannen" than "cuil bartha". Cuil bartha is just not a right translation as now it is basically the infinitive bartha together with the Sindarin word for life, but it should be an adjective verb with some other rules, so I think taking "Cuil marthannen" is the safest option. Also, I actually don't see a lot of glosses saying that "cuil" means life, and I myself would sooner take "Cuith" for life. You could also use "Estel" as before you said you wanted something with hope. So, you could say either: "Estel marthannen" (Fated/doomed hope) or "Cuith (/cuil if you rather have that) marthannen" (Fated/doomed life). Hope this helps!