What's behind your question Trills? If you have any shred of a doubt, then despite all the cutesy answers on here, I would strongly advise you to take your time. 
Before marrying:
Make sure you have a sole bank account
Do not have a non-signatory joint account
Separate, rather than lump together, any savings you have individually.
Have a will in place.
Have a proper discussion about children - do you both want them/not want them and either way who can compromise? Rough timeline?
Discuss, before marrying, how each of you might handle a possible break up so that there is some informal blueprint in place to help limit nastiness.
(how you would share bills/childcare etc. No slagging on social media)
Set some sexual boundaries:
eg, anal sex - yes or no or sometimes or over my dead body etc?
Porn? (ditto)
Discuss sex frankly - what each of you likes and doesn't like, needs more/less of.
Set some householed boundaries/agreements:
Fair share of housework if you live together?
No introducing no partners very quickly if you split?
Discuss expectations.
If you were splashing out on a mercedes you would want to know its capabilities, flaws and the longevity of its engine.
You simply must do the same in deciding to get married.
Of course, Love comes first. Love is everything. But rationality, realism and some degree of agreed values and boundaries must go hand in hand with the two of you as you step up to the alter.