There are two adjustments, one for shift lever to clutch basket rod preload to disengage the clutch, and another for engagement rpm. Because it is not just a grab a wrench and screwdrive and start to fiddle procedure I would recommend you pick up a service manual and follow the steps outlined.
If the clutch pack has been allowed to slip very much, you may have to change the clutch plates and steels, and perhaps even the preload springs. The manual will outline how to check each item.
The Lakota is a very good ATV and capable of a lot more performance than many realize. Do a web search for ATV Connection Magazine and for their articles on turning one up a bunch, you will not be sorry.