3.5 SRD said:However, some items made for wearing must still be activated. Although this activation sometimes requires a command word (see above), usually it means mentally willing the activation to happen. The description of an item states whether a command word is needed in such a case.
Unless stated otherwise, activating a use-activated magic item is either a standard action or not an action at all and does not provoke attacks of opportunity, unless the use involves performing an action that provokes an attack of opportunity in itself. If the use of the item takes time before a magical effect occurs, then use activation is a standard action. If the item’s activation is subsumed in its use and takes no extra time use activation is not an action at all.
Diirk said:Just make it use activated isntead of command word, like boots of haste. Then you just need to figure out what the use is.. something like flexing your muscles in a particular way, or tapping it.. I'm sure you can come up with something that sounds neat and could still reasonably be considered a free action.
3.5 SRD said:Boots of Speed: As a free action, the wearer can click her boot heels together, enabling her to act as though affected by a haste spell for up to 10 rounds each day. The duration of the haste effect need not be consecutive rounds.
Moderate transmutation; CL 10th; Craft Wondrous Item, haste; Price 12,000 gp;Weight 1 lb.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.