As a starting point, the 'one size fits all' Universal spray waxing kit is a good option for it's ease and quick application with very acceptable results for your stated needs. For the Maplus Quick & Standard Application, here
are the steps.
Go easy on the base cleaner (or use the Bio Citron or Citrus) and applying the universal spray over a harder base wax would be my preference, but if you are consistent with application and pay attention relative to snow abrasiveness and and use, the spray or liquid will be fine and almost too easy to use. You can always reapply at the hill if the snow is very coarse.
Here is the EpicSki Maplus test
and my son's science project thread
for additional spray and liquid insights. FWIW, per Maplus' testing run by the Product Manager, if consumers and competitors only based their wax purchases on durability and performance, Maplus would prefer to simply manufacture liquid waxes due to Maplus' superior high melt waxes in liquid form. Adding heat increase the durability to the liquids to beyond that of comparable solids (hot waxing).
As dumpy pointed out, the waxing is but one component. During a couple recent tuning clinics, the waxing was the preferred first step for those new to tuning, waxing and base prep. When I went from hot waxing techniques to the liquids, the simplicity and dramatic time savings got the 'wows and thumbs up'. I've tried to dispute the testing and potential 'hype' by comparing solids to the Maplus liquids and haven't been able to even with a typical old school bias (ad enjoyment) towards hot waxing.
Supporting your families skis for basic waxing and many tasks does not need to be complicated or anything more than simple tip and tail supports from basic materials readily at hand. When and if you move to edge tuning, scraping and brushing, securing the the skis becomes important.
I think the main thing is that your are stepping towards taking care of your boards start simple and evolve over time and bump it up a notch when it feels right.