By warming the solution above ambient temperature and then saturating it, I was trying to avoid just what you experienced. By keeping the saturation point high, the reaction will not reverse and crystallization will continue.
Some people just let evaporation solve the problem.
In college we accidentally grew some really nice potassium chloride crystals by failing to cover a beaker of solution. All the water evaporated over time and the bottom of the beaker was lined with some really nice crystals. As to the borax, I just played around with heating and recharging the solution as a way to get some impressive crystals to grow a bit faster. My own impatience aside, young students like to see results quickly. When you get results that can be clearly seen the next day and can be seen daily, their interest stays high.