Easy SP
Use the following trick to get very early party SP. Just outside the Urd Falls Cave as you are moving toward the downed ship is a save point. To the east side of this save point are two bug encounters that are very close to one another. You will need these two monsters to create the ambushes you need to fill up your bonus board. First, save the game. Reload the data to clear your current bonus board. Next, draw the two bug encounters together, then initiate combat. As you fight these battles, do not fulfill any bonus conditions (do not defeat multiple enemies with one strike, end the battle on a critical hit, or down an enemy using only Special Arts). When the second battle in the ambush begins, you will gain one green bonus tile for the ambush. Win this fight, collect your reward, then enter the Urd Falls Cave. Turn around and exit. Go back to the two bug encounters and repeat this process thirteen more times. If you can manage to not gain any other bonus tiles, you will have a bonus board filled with green tiles, each granting 1 SP at the end of every battle (giving you a total bonus of 14 party SP for each victory). You may consider saving two slots at the top or bottom to fill with HP/MP regen tiles, but this is entirely optional. Now, simply wander around, fighting everything in sight. The critical hit rate on all the monsters is extremely low but you may wish to switch over to Reimi and avoid contact with the enemy all together. In about an hour, you will have in excess of 500 party SP. Your experience and Fol levels will be rising as well, making the coming Boss fight easier. You can spend the party SP to increase Edge and Reimi's skills and still have more than enough for Faize and Item Creation. If you are really dedicated, you can max out your current skills as well as the purchasable skills in the alien base after you defeat the Boss and return to the crash site, and still have an enormous amount of party SP at your disposal.
Use the following trick for easy SP, experience points, and Fol. At the start of Disc 2, you will reach a town called Tropp. Before you enter Tropp, you will see two Albero di Anima's next to each other to the right of the entrance. A battle with these one of these two will almost always result in an ambush giving you a SPx1 bonus on the bonus board. When the bonus board is filled, after every battle you will receive about 2,500 in experience points, 2,000 in Fol, and 14 SP points. Just go back to Tropp, where the inn is very close, then exit to respawn the enemies. Repeat this as desired.