Level 260 can be split into two stages: clearing the obstacles (chains and boxes) in the middle and collecting the butterflies on the sides.
The main obstacle of the first stage is the narrow passage in the middle part of the field blocked by two boxes with two layers. You need to plan every move carefully and see the potential consequences. It’s not necessary to get access to all the 4 portals at once, but it’s also not advised to leave a portal closed for long.
The second stage is collecting the butterflies. There can be 4 butterflies present on the field at the same time, so it’s best to keep the cycle going. In some cases, a butterfly may be heading for a potential match, though keep in mind that the regular pieces and butterflies alike can fall because of other matches below. Don’t forget about the center of the field — you can always use that space to create power-ups that can travel down through the portals because of matches in the fields to the left and right.