Henceforth / be earls, / the first / that ev/er Scotland
In such / an ho/nour named. / What’s more / to do,
Which would / be plant/ed new/ly with / the time,
As call/ing home / our ex/iled friends / abroad
That fled / the snares / of watch/ful ty/ranny;
You see that dividing is not a difficult task.
You might want to consider looking for a different set of lines, depending on how regular you want them to be. The first line of these has an extra syllable at the end (which is allowed, if it's unstressed). It also has an irregularity or two in the rhythm: "Henceforth" is a trochaic or (or maybe spondee) foot; and the last two syllables of "tyranny" really don't have much stress, but are more trochaic than iambic.
But it's actually pleasant to have the rhythm a little less completely pinned to the basic iambic pattern.
In such / an ho/nour named. / What’s more / to do,
Which would / be plant/ed new/ly with / the time,
As call/ing home / our ex/iled friends / abroad
That fled / the snares / of watch/ful ty/ranny;
You see that dividing is not a difficult task.
You might want to consider looking for a different set of lines, depending on how regular you want them to be. The first line of these has an extra syllable at the end (which is allowed, if it's unstressed). It also has an irregularity or two in the rhythm: "Henceforth" is a trochaic or (or maybe spondee) foot; and the last two syllables of "tyranny" really don't have much stress, but are more trochaic than iambic.
But it's actually pleasant to have the rhythm a little less completely pinned to the basic iambic pattern.