Be helpful or useful.

Roget 707: aid, assist, help, succor, lend one's aid; come to the aid etc. n.. of; contribute, subscribe to; bring aid, give aid, furnish aid, afford aid, supply aid etc. n.; give a helping hand, stretch a hand, lend a helping hand, lend a hand, bear a helping hand, hold out a hand, hold out a helping hand; give one a life, give one a cast, give one a turn; take by the hand, take in tow; help a lame dog over a stile, lend wings to.    relieve, rescue; set up, set agoing^†, set on one's legs; bear through, pull through; give new life to, be the making of; reinforce, reenforce, recruit; set forward, put forward, push forward; give a lift, give a shove, give an impulse to; promote, further, forward, advance expedite, speed, quicken, hasten.    support, sustain, uphold, prop, hold up, bolster.    cradle, nourish; nurture, nurse, dry nurse, suckle, put out to nurse; manure, cultivate, force; foster, cherish, foment; feed the flame, fan the flame.    serve; do service to, tender to, pander to; administer to, subminister to^†, minister to; tend, attend, wait on; take care of etc. 459; entertain; smooth the bed of death.    oblige, accommodate, consult the wishes of; humor, cheer, encourage.    second, stand by; back, back up; pay the piper, abet; work for, make interest for, stick up for, take up the cudgels for; take up the cause of, espouse the cause of, adopt the cause of; advocate, beat up for recruits, press into the service; squire, give moral support to, keep in countenance, countenance, patronize; lend oneself to, lend one's countenance to; smile upon, shine upon; favor, befriend, take in hand, enlist under the banners of; side with etc. (cooperate) 709.    be of use to; subserve etc. (instrument) 631; benefit etc. 648; render a service etc. (utility) 644; conduce etc. (tend) 176.    ... show more

Roget 631: subserve, minister, mediate, intervene; be instrumental etc. adj.; pander to; officiate; tend.   

Roget 644: be useful etc. adj.; avail, serve; subserve etc. (be instrumental to) 631; conduce etc. (tend) 176; answer, serve one's turn, answer a purpose, serve a purpose.    act a part etc. (action) 680; perform a function, discharge a function &c.; render a service, render good service, render yeoman's service; bestead^†, stand one in good stead be the making of; help etc. 707.    bear fruit etc. (produce) 161; bring grist to the mill; profit, remunerate; benefit etc. (do good) 648.    find one's account in, find one's advantage in; reap the benefit of etc. (be better for) 658.    render useful etc. (use) 677.    ... show more