Disclaimer: as noted in the comments below, this technique requires a fair amount of baking experience, care, and to some degree, luck.
One helpful technique used for butter-creaming is to chop the butter into small pieces, place over a pan of softly simmering/hot water, and whisk until the butter is in a creamed state (with care taken not to melt the butter; usually the butter has to be taken off the double-boiler a few times to whisk any melted butter back into the rest if that occurs); the end result should be an opaque and thick bowl of creamed butter with a consistency ranging from a thick custard to standard, machine-creamed butter (the whisking helps retain form, and a lower temperature can help prevent the butter from getting too warm). The sugar can then be folded in until homogenous and whisked further until peaks are formed (if they have not already).
There is a fair amount of sugar in that recipe compared to butter, so creaming it may require more effort. Also, using a finer-grained sugar ("bakers'" sugar, for example) can help getting the mixture to a creamy state as the sugar crystals can more readily dissolve and dissociate into the butter; this however can require more vigorous whisking to introduce the needed air bubbles into the mixture since the finer grains of sugar will introduce less air when mixed.
This technique also comes especially handy when baking in batches that result in quantities of butter too large to cream in a standard standing mixer (and thus hand-creaming is required).